The Mark of Athena

''This article is about the book. You may be looking for The Mark of Athena (coin).''

The Mark of Athena is the third installment of The Heroes of Olympus series. It was released on October 2, 2012. The book continues where The Son of Neptune left off. The book is told from the points-of-view of Annabeth Chase, Leo Valdez, Piper McLean, and Percy Jackson.

Development
Rick Riordan has been working on The Mark of Athena since the completion of The Son of Neptune. While Amazon.com released information on the book, including page numbers, Rick mentioned that the book wasn't finished yet. So the information is deemed speculative.

During his tour to promote the last of The Kane Chronicles books, titled The Serpent's Shadow, Rick read part of the first chapter of The Mark of Athena. There, it is revealed that Annabeth Chase is one of the narrators. The cover and full first chapter were released on June 1st on the Disney Heroes of Olympus website.

On September 27th, Rick Riordan confirmed that there would be first US printing of 3.5 million copies.

Synopsis
"In The Son of Neptune, Percy, Hazel, and Frank met in Camp Jupiter, the Roman equivalent of Camp Half-Blood, and traveled to the land beyond the gods to complete a dangerous quest. The third book in the Heroes of Olympus series will unite them with Jason, Piper, and Leo. But they number only six--who will complete the Prophecy of Seven?"

The Greek and Roman demigods will have to cooperate in order to defeat the giants released by the Earth Mother, Gaea. Then they will have to sail together to the ancient land--Rome itself--to find the Doors of Death. What exactly are the Doors of Death? Much of the prophecy remains a mystery...

With old friends and new friends joining forces, a marvelous ship, fearsome foes, and an exotic setting, The Mark of Athena promises to be another unforgettable adventure by master storyteller Rick Riordan."

“Told from the perspectives of four different demigods, including Annabeth from Percy Jackson and the Olympians, The Mark of Athena unites the Greek and Roman main characters from The Lost Hero and The Son of Neptune. In a fantastical ship called the Argo II, seven demigods journey by air across the United States and by sea to Rome on their quest to defeat the earth mother, Gaea. Meanwhile, war is breaking out between the Roman and Greek demigods they left behind, and only Annabeth holds the key to restoring peace.”



"Annabeth is terrified. Just when she's about to be reunited with Percy, after six months of being apart, thanks to Hera, it looks like Camp Jupiter is preparing for war. As Annabeth and her friends Jason, Piper, and Leo fly in on the Argo II, she can't blame the Roman demigods for thinking the ship is a Greek weapon. With its steaming bronze dragon masthead, Leo's fanatical creation doesn't appear friendly. Annabeth hopes that the sight of their praetor Jason on deck will reassure the Romans that the visitors from Camp Half-Blood come in peace.

And that's only one of her worries. In her pocket Annabeth carries a gift from her mother that came with an unnerving demand: Follow the Mark of Athena. Avenge me. Annabeth already feels weighed down by the prophecy that will send seven demigods to find and close the Doors of Death. What more does Athena want from her?

Annabeth's biggest fear, though, is that Percy might have changed. What if he's now attached to Roman ways? Does he still need his old friends? As the daughter of the goddess of war and wisdom, Annabeth knows she was born to be a leader, but never again does she want to be without Seaweed Brain by her side.

Narrated by four demigods, The Mark of Athena is an unforgettable journey across land and sea to Rome, where important discoveries, surprising sacrifices and unspeakable horrors await. Climb aboard the Argo II, if you dare..."

Plot
While getting ready to land at Camp Jupiter, Annabeth Chase prepares by making sure the back-up plans are ready in case something goes wrong, as well as the back-ups to the back-up plans. While Leo Valdez is flying the Argo II with a control system that involved Wii remotes, a dubstep sound board, a keyboard, and a monitor, Annabeth tries to keep Gleeson Hedge from attacking the first thing he sees by making him watch reruns of mixed martial arts championships in his cabin. Jason Grace prepares by putting on a purple toga over his orange Camp Half-Blood t-shirt and Piper McLean practices her lines for the landing. As Annabeth watches Jason, she wonders if this could all be a trap, as she was still a bit distrusting of Jason because he seems too perfect. She is also reminded of how much she misses Percy Jackson every time she looks at Jason.

Annabeth also mentions feeling a mysterious chill, as if "an evil snowman had crept up behind her and was peering over her neck." Annabeth wishes she could pray to her mother, but this would be impossible, as Athena had appeared to her about a month earlier -- an encounter Annabeth describes as horrible. Athena also had given Annabeth the worst present of her life during this meeting. Soon, the horns from Camp Jupiter blew from below as the campers had spotted the Argo II.

Annabeth Chase is amazed by the size of Camp Jupiter, which is twice the size of Camp Half Blood, and notices the landmarks that Jason had told her about. She sees evidence of the Romans' recent battle, including the cracked dome of the Senate House.

An explosion nearly knocks Annabeth overboard, and Terminus, the Roman god of boundaries, appears on the Argo II. He shrieks that he will not allow any weapons inside the Pomerian Line, and grumbles at Jason for consorting with the enemies of Rome, referring to the Greek demigods. Piper tries to charmspeak Terminus, but he slaps her dagger out of her hand with magic for her impertinence. Since New Rome is still recovering from the recent battle, Terminus announces that if he was at his full strength, he would have already blasted the "flying monstrosity" out of the sky, to which Leo takes offense to. Annabeth tries to regain control of the situation and calm everyone down by introducing herself to Terminus, but the god finds Annabeth being the daughter of Athena, the Greek form of Minerva, to be "scandalous." However, before Annabeth can question Terminus on what he means, Jason interrupts and asks for permission to land inside the Pomerian Line.

Terminus instead tells them to "surrender, then leave," and 'slaps' Leo's face for asking what the options are. This interests Leo even more and he asks if he can take a look at Terminus' gears, thinking he is an Automaton. Terminus makes Leo drop the screwdriver, announcing "weapons are not allowed on Roman soil inside the Pomerian Line," which includes the Argo II itself, as the whole ship is a weapon. Annabeth spots Percy walking with Frank and Hazel as if they were best friends, and Annabeth knows she had to reach him, as she was so close. She also notices that he is now a Praetor, as he is wearing a purple cape just like Jason's.

Annabeth orders Leo to stop the ship as she asks Terminus whether there is a rule against the ship hovering over New Rome, to which Terminus says there is not. Annabeth then tells Terminus that they will keep the Argo II up in the air over New Roman and use a rode ladder to reach the forum. She also promises Terminus that all the weapons will stay on the ship, as long as the legion reinforcements will honor the same rule, which Terminus agrees to as he cannot tolerate those who break the rules.

When questioned by Leo who asks if this was a good idea, Annabeth clenches her fists to stop them from shaking. She feels the cold presence, which seems to be laughing at her and the bad choices she is making. But she knows that Percy is down there, and that she has to reach him. She replies that it will be fine and Terminus will make sure that both sides will obey the rules, if Terminus agrees. Terminus sniffs, but agrees "for now," and allows them to climb down the ladder to New Rome, but pleads them to not destroy his city.

The five demigods climb down a ladder and walk through the crowds of Romans to Reyna, the praetor, and Percy. Reyna starts to speak, but Percy and Annabeth run into each others' arms, and kiss each other. She then suddenly suddenly slams Percy into the stone pavement, sending the Romans into a fury, and tells him to never leave her again. Jason then introduces the rest of the demigods. After the introductions, Reyna calls forth the Centurions to discuss something and tells the spirits in the kitchen to prepare a welcome feast. Octavian is flabbergasted that Reyna is letting the "intruders" into camp. Reyna dismisses him to go read his auguries and they go to the feast.

Reyna calls a toast for friendship, and soon after all parties start to exchange stories about what they had been going through for the past year. Eventually, Octavian recites the Prophecy of Seven, but Annabeth interrupts him and finishes the sentence. They realize that the Prophecy of Seven is meant for Greeks and Romans to combine forces to close the Doors of Death. Tyson then calls for his brother, Percy, to tell him that Ella is scared. Ella starts mumbling about about different ships that have sunk and notices Annabeth. Once she does she starts reciting a prophecy. Because no one except for Percy, Hazel, and Frank knows that she had once read the Sibylline books, they attempt to make it sound like she is spouting nonsense. After having convinced Octavian it was not a prophecy, Tyson and Ella shadow travel with Ms. O'Leary to somewhere safe.

After the ordeal, Octavian still does not trust the Greeks. In order to prove to Octavian that the Argo II is not dangerous, Leo takes Octavian on board the ship and shows him around. Jason then asks Reyna if it is alright for him to show Piper around, oblivious to the tension between Reyna and him. Percy, also wanting to show Annabeth New Rome, attempts to leave, but Reyna stops Percy and tells him that she wants to talk to Annabeth privately.

While Reyna is walking with Annabeth through New Rome, she calls for her dogs, Aurum and Argentum. The girls discuss the differences between Minerva and Athena. Reyna denotes there are no children of Minerva at Camp Jupiter, and that if they were to come there, they would be artists -- not warriors or leaders on quests. Annabeth then realizes that she has met Reyna before at Circe's Island. They walk all the way to the Garden of Bacchus, which is Reyna's favorite place in Camp Jupiter, and appreciate the view. Reyna explains that she had wanted to talk to Annabeth to learn the truth. Instead of Annabeth feeling bad about her not being able to trust anyone at Camp, she talks about her family, growing up, and adventures in Camp Half-Blood.

Throughout the conversation, Reyna mentions that while she was on Circe's Island, she met a son of Athena, who washed up on the shore and rambled about the Mark of Athena. Then, a sudden, large explosion makes a crater in the forum of New Rome. The Argo II then proceeds to attack the city. Reyna and Ananbeth rush down to the forum. Since Roman's are not allowed any weapons inside the Pomeranian Line, they start to throw food, rocks, and plates at the Greeks. Piper and Jason try to calm the angry mob by telling them they would never attack New Rome, but fail. Right outside the Pomerian Line the Roman's set up catapults to fire on the attacking Argo II.

Annabeth then sees Percy using water from a fountain to dose the angry mob of Romans. Octavian comes down the ladder screaming that Leo has fired on everyone. Percy asks if Hazel and Frank are coming with them on the ship, to which the two say yes. Hazel calls for Arion and distracts the crowd by riding straight through it. Frank, in attempt to let Percy and Annabeth climb the rope, changes form into a drakon. Once Percy and Annabeth are up, Leo is tackled to the ground by Percy and falls on his head. Annabeth then takes charge of the ship and leaves Camp Jupiter as quickly as possible.

Once Leo finally wakes up he is questioned by Annabeth about why he set aim at the Roman Camp. Leo responds by saying that he has no idea why he did. Leo talks about how he felt a cold presence and then doesn't remember anything. Frank comes from below deck to aboard the Argo II and tells Annabeth that she should really come downstairs. Before Annabeth leaves, she asks Frank to watch Leo. After a brief silence Frank asks Leo if he's sure that his name isn't Sammy. Leo gives him a questioning look and tells him no. Leo tells Frank that he needs to do a damage report with Festus. The boys proceed to go check on Festus.

As they walk up to Festus does a 80 degree turn to look at them. Frank, startled, screams that "it's alive". Leo continues to receive the damage report from Festus and states that they need tar, lime, and Celestial Bronze. Festus notices that "AY-zuhl" is down below. Frank tells Leo that they need to land to pick up Hazel and Arion. Before they land, they do a scan to make sure they can find all the items in a near by area.

While the scan is happening, Annabeth and Percy walk back up to report that Jason is doing well and that Piper is watching over him. While Leo is telling Annabeth about the damage report, Festus finds an area where all the items are. The area is Salt Lake, Utah. While descending everyone went downstairs to strap themselves in for an ugly landing, except for Coach Hedge who continues screaming, "Bring it on, Lake!"

Annabeth, Percy, and Frank leave to get tar, while Leo and Hazel leave to find Celestial Bronze. Piper stays on board and waits for an unconcious Jason to wake up, along side Coach Hedge.

While searching for the bronze, Hazel and Leo encounter Nemesis, who gives Leo a fortune cookie, telling him to open it when he really needs her help, but says that the help will also have a high price.

Hazel and Leo continue on, and come across Echo, who is trying to save Narcissus, both of whom have been brought back from the underworld. Narcissus is being obsessed over by nymphs, while he stares at the reflection of himself through the lake, into a large sheet of Celestial Bronze.

Leo distracts Narcissus and the Nymphs, with the help of Echo, while Hazel retrieves the Celestial Bronze. Leo and Hazel are being pursued by the upset Narcissus and Nymphs, while they run back toward the Argo II.

Piper continues to take care of the unconscious Jason. Piper looks into Katoptris and sees many unsettling images, along with a vision of a man in purple next to a Topeka 32 road sign and a man dressed in purple clothes. After Jason finally wakes up and the two groups return, the seven convene and then decide to head to Topeka to meet with Bacchus. Leo brought the ship in for a landing, but unfortunately landed about eight miles from where they needed to be. Jason and Percy each say they have a friend who could give them a ride, resulting in them making a bet to see who's friend would get there first. Jason whistles for Tempest while Percy calls for Blackjack, with Blackjack flying out of the sky mere moments before Tempest. Percy rode on Blackjack to the right location while Piper and Jason rode on Tempest down below. When they get to the mile marker next to a wheat field, Percy comments that there is no sign of the "wine dude." At that moment, a very annoyed Bacchus exited the field and claimed he was waiting for Ceres to talk about how Gaea was destroying the plants. Percy and Bacchus get off to a rough start, bantering back and forth with each other, causing Bacchus to become incredible annoyed, even threatening to turn him into a dolphin. When Piper realizes that Percy isn't helping matters, she interrupts the two and tells Bacchus she had a vision that he would help them. Bacchus starts to give them advice about how to through a good party, but Piper explains that they need help on their quest. Bacchus remembers when he first fought the giants back when he was only a demigod, helping to defeat the twin giants Ephialtes and his brother Otis. Piper takes this as a sign that he is part of their quest, but Bacchus says that he is no longer a demigod and doesn't do quests anymore. When Piper tells him that he has to help them, he comes angry and claims he would only help if they offered him tribute, something he claims they would never be able to do. However, he does tell the group to seek out Phorcys for information on Gaea, before realizing that Ceres would only be late if she felt there was a trap waiting for them, causing the god to flee the area.

Just after the god has left, Gaea makes her move as two more Eidolons take control of Jason and Percy. Gaea tells Piper that she only needs a boy and a girl demigod, and that Piper would have to choose which of the boys will die. Piper is unable to make the choice and tries to stop the boys from killing each other, leading to Percy knocking Jason off Tempest. Jason then knocks Percy off Blackjack with a bolt of lightning. Just as Jason goes to finish him off, Piper makes him stop, giving Percy the opportunity to knock Jason out by sweeping him off his feet. As Percy goes to kill Jason, Piper manages to gain his attention long enough for Blackjack to knock Percy out with a hoof to the head. Piper then has Blackjack carry them back to the Argo II, where they are treated for their injuries.

While they no longer seem possessed, Jason apologizes to Percy saying that he could have killed him, but Percy claims that he also could have killed Jason. Piper intervenes saying that the demigods ought to talk about what they learned from Bacchus and Annabeth called a meeting in the Mess hall. At the meeting, the discuss how the Eidolons had taken control of Percy and Jason, as well as Leo who is revealed that he wasn't responsible for the attack on Camp Jupiter. However despite knowing the truth, they have no evidence to support this and Octavian has gotten the Romans so frenzied, that they wouldn't listen anyway. Jason also informs them that the Romans wouldn't follow them into the Mediterranean Sea, as it is considered off limits, meaning that if they go there they would be considered traitors to Camp Jupiter, but the Roman troops wouldn't follow them. They also talk about the twin giants and how Gaea wants two demigods, leading Leo to remember what Khione said at the Wolf House, how Jason's blood would taint the area for generations. Percy also remembers how Polybotes wanted to capture Percy and use his blood to water the stones of Mount Olympus and wake Gaea. Percy suggests that until they figure out what Gaea wants, they should try their best not to be captured. They end the meeting by saying they need to find Phorcys, but Piper stops them as they get ready to leave. She tells them that the Eidolons are still here and she has a plan for getting them off the ship. She uses her Charmspeak to call them out, leading Percy, Jason, and Leo to once again be controlled by the spirits. While the Eidolons fight back against Piper's charmspeak, they eventually are forced to swear on the River Styx never to take control of an Argo II crew member or return to the ship, causing the Eidolons to give up their borrowed bodies.

That night Percy has a dream about his time in Alaska, about how he almost drowned in muskeg and what it really meant to suffocate. However, the dream eventually turns to Otis and Ephialtes, who reveal that they are preparing to destroy Rome on the first of July. As they leave, Percy sees a jar and pills himself inside so he could see what was there. Inside, he found Nico diAngelo in a meditative state, using Pomegranate seeds to keep him alive as the jar had very little air, leading Percy's fear of suffocation to scare him. While he calls out to Nico, he doesn't hear him and remains in his trance. As Percy calls out to him, saying that they will save him, Percy is woken up by Annabeth who tells him to brush his teeth and hair as she wants to show him something.

Annabeth takes Percy down to her favorite spot on the ship, the stables. Leo had designed the stables for pegasi, which are free spirits and prefer to fly free, meaning the stables are always empty. They wrap themselves in a blanket and look down through the clear bottom of the boat. Annabeth asks Percy is this place reminds him of anything, and Percy thinks back to the time they were in the Kindness International truck, but can't figure out why such a depressing time would lead to the stables being her favorite spot on the ship. She explains that the back of that truck was the first time they really connected, pulling out her camp necklace to see the ring from her dad. Percy then tells her about her dream and Annabeth asks him if Poseidon has talked to him at all, which Percy says he hasn't. When he asks her if she had heard from Athena, she admits that they had a fight and she has been having nightmares, but the two agree not to talk about any more depressing things. The two eventually fell asleep, leading to the rest of the crew to think they were kidnapped at some point in the night until Frank found them. As punishment for scaring everyone, Coach Hedge grounded the two, telling them that they weren't to be alone together anymore.

Once they arrive in Atlanta to search for Phorcys like Bacchus had suggested, Coach Hedge refuses to allow Annabeth and Percy to go search together, so Hedge, Frank, and Percy go down to the city instead. When they ask a lady named Esther if she knew where they could find salt water in a landlocked city, she suggests the aquarium and drops them off herself. Once in line, they notice they have very little mortal money and can't pay for entry. Just then, a lady with a name tag that says Kate appears and swoops up the three denarii Frank was holding and offers them the VIP tour. Hedge notices that Kate is not a human and they begin to expect a trap, but follow her in hopes of finding Phorcys. She shows during the tour that she has expert knowledge on larger sea animals, but cares little about smaller fish. Once they reach the sea monster exhibit, it is shown that several of the monsters are tranquilized. Kate also drops a few hints that she know about the three already, as she knows Percy is a son of Poseidon and Hedge is a satyr. Phorcys appears soon after and Kate points out that their name tags are wrong, revealing herself to be Keto, the mother of sea monsters. Phorcys becomes annoyed with her more informational stance on the tour as he feels it will bore customers, but her and Hedge walk off to talk some more, leaving Frank and Percy with Phorcys.

Frank and Percy flatter Phorcys' use of fireworks and a disco ball, getting him to talk about Ephialtes and Otis, twin Gigantes that together make up the anti-Dionysus. He also explains that they have a prisoner trapped in a bronze jar to use as bait for the crew of the Argo II. When asked about Gaea's plans, he explains that her plans have many layers and that she placed a bounty on a few demigods. He also mentioned that even if they found the map in Charleston leading to the Athena Parthenos in Rome, they would be doomed anyway before joking about it with Frank. After that, he continues the tour and leads them to another exhibit, but it turns out to be a trap and the two are trapped in a large tank, as Phorcys plans on having daily shows where the two fight sea monsters. He leaves them trapped, but Hedge and Keto pass by the tank a moment later. Percy manages to get Hedge's attention, and he acts calmly before kicking Keto in the back of the head. The three then attack the same spot of the tank and free themselves before escaping back to the Argo II and they fly off to Charleston.

On they way, they begin to talk where this map might be, and Jason suggests Fort Sumter or a place called the Battery, a place him and Reyna had been before. When they were there, they saw a ghost and Reyna talked to it alone, but acted differently ever since and refused to tell Jason what it said. However, they also learn that the Roman eagles are right on their tail. To try and lead them away, Leo sends Buford on a decoy trail with a bag of dirty laundry to lead the Roman eagles away and maybe delay them.

That night, Annabeth remembered her meeting with her mother a few months ago. After leaving Sally's apartment, she went to take a train at Grand Central Station and saw her mother looking at a map. She seemed confused and didn't even recognize Annabeth when she called out to her. Annabeth questioned if she was actually Minerva, her Roman form, but she yells at her to never call her that. She claims that she was Athena before the Romans destroyed Athens, took away her title as a war goddess, and stole her statue. In order to avenge her, she orders Annabeth to follow the Mark of Athena and hands her a small subway token that changes into a small silver coin. When Annabeth said that she needed help finding Percy, the goddess claims that she cares nothing for him and if he joined the Romans, then he should perish with the rest of the Romans. If Annabeth would help them as well, then Minerva claimed that she is no child of hers. Minerva then turns back to subway map and looks just as confused as before.

Back in her cabin, Annabeth hears a knock on the door and Frank walks in, asking for advice. He shows her a pair of Chinese finger cuffs that he couldn't figure out the trick to earlier (something some of the others laughed about). Annabeth uses her laptop to scan the toy and show Frank how it works. She explains that when he pulls tight, the fabric will tighten as well, preventing the fingers from escaping. The only way to get out is to push your fingers together and take it off that way. While Frank is grateful, he wonders if Annabeth really had to bring it up on the computer and could have just shown him. Annabeth admits she could have just done that as well, taking some advise from Frank to just keep it simple. He is also about to ask her if she could help him find an answer to prevent his stick from burning up, but is cut short when the dinner bell rings.

Once docked in the harbor at Charleston, Annabeth, Hazel, and Piper McLean agree to search for the ghost of the Battery while Frank, Leo, and Jason agree to search the museum for any sign of the map. Percy on the other hand went into the harbor to see if there was a way to free the monsters and creatures back in Atlanta. When they see the ghost, Hazel points out that there is no way it was a spirit as no spirit glows that brightly. They approach the spirit who is actually Aphrodite, Piper's mom. She sits them down for tea and begins to give Annabeth and Hazel some beauty tips, before Piper stops her after feeling embarrassed of her mother's actions. When Annabeth asks if she is Aphrodite or Venus, she explains that she never really changed when the flame of Western Civilization moved to Rome, because love is universal so she is both. That is the reason why she isn't affected by the Civil War as much as the other gods. Hazel protests, saying they aren't at war yet, but Aphrodite only compliments her optimism and says that war is coming, along with many heartbreaking days. After remembering all the parties in the old days of the south, Piper gets her back on track and Aphrodite says she is here to help as Hera has been kicked off of Olympus by the other gods. When she mentions the fight between Athena and Annabeth, she explains that Athena was the most Greek of all gods and the Romans insulted her by limiting her to crafts and cleverness. From this, Annabeth figures out that what they are searching for is the Athena Parthenos, the statue of Athena that went missing thousands of years ago. The Greeks never forgave the Romans for this insult, while Athena and her children made it so the two groups ended up fighting. Just then several war eagles appear and Aphrodite tells them that the map is at Fort Sumter, the location of the first battle of the Civil War.

As they race for the ship, Octavian cuts them off with two bigger guys to back him up. When they try to explain that Leo was controlled by the Eidolons, Octavian says they can't hear them because they have wax in their ears (so they can't be controlled by Piper's Charmspeak). Annabeth tosses her knife into the water when Octavian tells them to lower their weapons. Just as Octavian tells the other two to lower theirs, the water around the rock erupts and traps the Roman soldiers in a small whirlpool that Percy creates. Percy then hands Annabeth her dagger with a poker face and says, "You dropped this." They climb onto the Argo II and sail toward the fort, sending an Iris Message to Jason and his group to warn them. When Jason, Frank, and Leo are trying to make it back to the ship, Hedge fires a shot at the Romans which causes the group to fall behind the walls of the fort. Annabeth orders the demigods on board to defend the ship while she rushes into the fort to find her friends. Once inside, she orders them to the ship while she goes to find the map. She enters a room looking for the map and the walls begin to fill with spiders. As Annabeth can't move from fear, Gaea tells her that she will meet the weaver soon and how she would preferred Annabeth as a sacrifice. Gaea's voice fades and is replaced by a flaming owl that burns away the spiders and leads Annabeth to the map.

Once she has the map, she is confronted by Reyna with her two dogs, Argentum and Aurum. When Annabeth starts to explain how Gaea is trying to separate the camps, Reyna tells her to save it for her trial. When Annabeth claims that the Giants have won if they fight, Reyna says she has no choice as she can no longer control Octavian. If Annabeth agrees to return for a trail, she will be executed, but some kind of peace can be achieved. While Annabeth refuses, Reyna points out that this is the better option, and if Octavian does not have blood, his attention will turn to Camp Half-Blood instead. This saddens Annabeth, but she claims that she can fix the rift between the two camps and thus persuade Reyna to let her go, but says that the next time they meet, they will be enemies. Annabeth only asks that Reyna slow Octavian down before reaching the camp. After their meeting, Annabeth runs back to the ship while Jason and Percy call forth a storm to push the Romans back. Once Annabeth is on board, they sail off to the Mediterranean Sea and Rome in order to save Nico and find the Athena Parthenos.

They reach the Mediterranean Sea and see the Pillars of Hercules. Guarding them is Hercules. The heroes then decide to send their best speakers, Jason and Piper, to talk to the god. They talk to him for awhile and the god says that he will give them an easy quest since one has to complete a quest to get permission to enter the Mare Nostrum. Jason mentions Hera however and since Hercules hates the goddess, he changes his mind a gives them a harder quest. Their quest is to get the horn of Achelous to humiliate Achelous even more as Hercules had already taken his other horn.

The two demigods get the horn and go meet Hercules again, who gives them permission to pass as they had retrieved the horn. He then asks for it, but Piper refuses to give it to him as he doesn't deserve something as precious as the cornucopia. This angers Hercules and he prepares to kill them all, but Piper releases an unprecedented amount food from the cornucopia, which completely buries the god. Jason then flies them to the ship and they start to take off. Hercules manages to escape from under the food, but it quickly knocked back down as Percy hits him with a ten-foot tall wave of water. As they fly off, Hercules starts to chuck the food at the ship, managing to lodge a few coconuts in the hull of the ship, but they manage to escape none the less.

After sailing into the Mediterranean Sea, the ship is frequently attacked by Stymphalian Bird, Venti, and a wild pegasus that stepped on Gleeson's enchiladas. Percy goes to sleep while Jason keeps watch and had a dream about Otis and Ephialtes talking with a figure he couldn't see. They report that the group should be at Rome a little after daybreak if they could get past the golden boy. Ephialtes reminds the figure that Gaea wanted Annabeth alive for the sacrifice, but the figure says that others could be used instead. Ephialtes simply says that Annabeth and Percy are preferred, but the figure shoos them away and the dream dissolves. Jason knocks on his door and tells him it is his tern to take watch, as they are now in water. Percy wakes up Annabeth and tells her about his dream. Annabeth makes Percy promise not to tell the others as his dream was about the Athena Parthenos and the others knowing would only scare them, as Annabeth needs to do this alone. Percy thinks on this, but has a strange feeling and orders the ship to stop. It was too late as another ship came out of the fog and rammed into the Argo II. Grappling lines attached to the rails and in an instant, the entire ship was overrun by dolphin warriors. Their captain soon arrives on deck and instantly disarms Percy, sending Riptide splashing into the sea.

The man introduces himself as Chrysaor, also known as the golden boy because of the golden Gorgon mask he wears in honor of his mother. Chrysaor's crew tie up everyone on board (except Frank) and start to ransack the ship, stealing anything worth value, including a box full of Greek Fire. Chrysaor begins to make plans, including selling Hazel Levesque and Piper McLean to Circe, while keeping Annabeth and Percy for a sacrifice to Gaea. Hazel and Piper begin to thrash around just as Riptide returns to Percy's pocket. Percy uses the distraction to try and surprise Chrysaor, but he is quickly defeated again. Having to think quickly, Percy begins to tell Chrysaor and his dolphin men that because the crew of the Argo II failed to finish their quest because of Chrysaor, their captain would be very upset. Chrysaor claims that there is no one else on their ship, but Percy says that a god only appears when they want, as their captain is Mr. D. The dolphin men become nervous as Dionysus was the god that originally turned them into dolphins, but Chrysaor tries to keep order. Percy goes on, saying that the god had driven Piper and Hazel mad a few moments ago when they thrashed around, that the cooler on the ship has a can of Diet Coke (Mr. D's favorite soda), and Dionysus would soon turn them all into dolphins as punishment. Frank then appears from his hiding spot and transforms into a dolphin. This scares the dolphin warriors off the ship and Chrysaor is backed into a corner by the crew. His mask is knocked off and he jumps over the side, escaping. Percy then sinks Chrysaor's ship by filling it with Diet Coke and offering it to Dionysus as a tribute.

The crew decide to go by air and Percy heads back to bed, but has a dream about Gaea. She shows him a vision of Camp Half-Blood turning to ash and dirt. She offers to spare this place if he brings Annabeth and himself to her willingly, but Percy wakes up and finds that they have arrived in Rome. They land in a park and start to make plans. Annabeth plans on going to the Tiber River alone, but Percy convinces her to allow him to go with her for protection, while Hazel, Leo, and Frank try and find Nico diAngelo by having Hazel try and sense him. Gleeson Hedge, Jason, and Piper would stay behind and watch the ship.

Annabeth is taken on the first part of her journey by the gods Rhea Silva (mother of Romulus and Remus) and Tiberinus (god of the Tiber river). Hazel, Frank and Leo head off to try to find Nico, but they instead find a secret underground room containing automatons constructed by Archimedes. The eidolons possess some of the automatons and attack the three, but Leo saves the day by using the fortune cookie to learn the activation code for one of the devices and destroying the possessed automatons with it, trapping the eidolons. Percy, Jason and Piper also try to find Nico and have to survive an attempt by nine angry nymphs to drown them. They free the nymphs, who then help them find the lair of the giants Otis and Ephialtes, who plan on destroying Rome in a great spectacle, and are holding Nico captive. Joined by Bacchus, who only agrees to help after he has been sufficiently 'entertained,' Jason and Percy kill the giants. Back on board the Argo II, Nico explains how he had been looking for the Doors of Death in the Underworld when he was sucked into Tartarus -- a trip he barely survived. Nico also says that the Doors open into the mortal world in the House of Hades, an underground temple in Greece.

Meanwhile, Annabeth follows the Mark of Athena into an underground labyrinth. She encounters the ghosts of followers of the foreign god Mithras cult, but escapes by collapsing the room, though she breaks her ankle in the process. She escapes from many spiders by making a woven bridge over a chasm, and finally finds the Athena Parthenos being guarded by the monster Arachne. Annabeth manages to trick Arachne into weaving giant Chinese handcuffs supposedly to prove Arachne's genius to the Olympians, but it is actually to make her remove the webbing from the statue and trap herself. Upon realizing that she has been tricked, Arachne angrily brings down part of the chamber, but the rest of the crew on board the Argo II arrive and send Arachne plunging down a pit that leads straight to Tartarus. Just as the group are loading the giant statue, Annabeth tumbles into the pit herself after her foot is caught in a web attached to Arachne. Percy tries to save her, but it quickly becomes apparent that he cannot. Telling Nico to lead the others to the House of Hades and vowing to never leave Annabeth again, Percy allows himself to fall into the pit with her.

The story ends with the remainder of the group vowing to continue on to Greece and close the Doors of Death before taking out the giants for good, trusting that Percy and Annabeth will somehow survive long enough to be rescued.

Chapter List
There are no chapter titles. Each chapter has a name of one of the main characters and is written in Roman Numerals. There are 52 chapters going alternately in the order of Annabeth, Leo, Piper, and Percy. Each character gets four chapters before it shifts to another character.

Prophecy
A prophecy by Ella the Harpy, while with Percy, Hazel, and Frank, refers to this as well. Translated from Latin to English, it says:

''Wisdom's daughter walks alone, The Mark of Athena burns through Rome. Twins snuff out the angels breath, Who holds the key to endless death. Giants bane stands gold and pale, Won through pain from a woven jail.''

Unraveling of the Prophecy

 * Annabeth, daughter of the wisdom goddess Athena, walks alone through the underground of Rome or, as she puts it, she doesn't have any special ability like the other six heroes do, which is why she walks alone.
 * The symbol of the Mark of Athena glows bright red like fire making seem like it burns through several places in Rome.
 * The twin giants Ephialtes and Otis take away Nico di Angelo's air by putting him in a jar. Angelo is Italian for "angel."
 * Nico holds the information to the Doors of Death.
 * Athena Parthenos is made of gold and ivory, which are like pale stones.
 * The statue was rescued by Annabeth Chase from Arachne. Despite Annabeth's broken ankle that caused her extreme pain, she managed to win the statue by getting Arachne to weave her own jail.

Main Characters

 * Annabeth Chase
 * Percy Jackson
 * Piper McLean
 * Leo Valdez
 * Jason Grace
 * Hazel Levesque
 * Frank Zhang
 * Nico di Angelo
 * Gleeson Hedge

Villains

 * Arachne
 * Gaea
 * Otis and Ephialtes
 * Phorcys
 * Keto
 * Narcissus
 * Chrysaor

Gods

 * Athena/Minerva
 * Dionysus/Bacchus
 * Aphrodite/Venus
 * Nemesis
 * Hercules
 * Terminus

Other Characters

 * Reyna
 * Echo
 * Octavian
 * Ella
 * Tyson
 * Dakota
 * Aphros
 * Bythos

Trivia

 * The Mark of Athena is the only book in The Heroes of Olympus series so far, where the character who narrated the first chapter does not narrate the last chapter.
 * The Mark of Athena shares some similarities to The Sea of Monsters:
 * A crew sail into the Sea of Monsters, the Bermuda Triangle in The Sea of Monsters and the original Sea of Monsters in the Mediterranean Sea in The Mark of Athena.
 * While Blackjack first appeared in The Sea of Monsters, he made his first actual appearance in The Heroes of Olympus series during The Mark of Athena.
 * Both books have a pirate (Edward Teach and Chrysaor).
 * At one point when talking about the Doors of Death, it is described as being a hole in a dam. Percy makes a dam joke, which no one understands and he says it is an inside joke, referring to his trip to the Hoover Dam in The Titan's Curse.
 * The four narrators of the book are all children of the Greek forms of the gods.