Luke Castellan

Luke Castellan is a son of Hermes who currently sides with Kronos. It is unknown if he is alive as Kronos is currently using his body as a shell to live in.

Early Life
Luke is the son of Hermes. Not much is known of his early life, but when he was about fourteen, Luke ran away from his mother's home in Westport,Conneticut. Later on, he met Annabeth, Thalia, and Grover Underwood. It is likely that he began to forge a romantic relationship with Thalia at this time. Together, the quartet traveled to Camp Half-Blood but were chased by monsters. They would have escaped, except for the fact that a cyclops stopped them so that monsters could catch up. The Cyclops held Thalia and Luke in the air to direct the monsters in their direction, but Annabeth saved them by stabbing the Cyclops in the foot. Thalia sacrificed her life so that Luke,Grover and Annabeth could get into camp without being killed. From that point on, Luke lived at camp all year round, presumably trying to reconcile with Thalia's "death".

The Lightning Thief
He was considered a protagonist in most of book 1, giving his magical flying shoes to Percy, but he revealed his true nature to Percy near the end of the book and tried to kill him by a pit scorpion. It became apparent that Luke had betrayed the gods and started to work for Kronos. These actions were motivated by the fact that Luke thought Hermes, his father, did not love him.

The Sea of Monsters
In The Sea of Monsters it was revealed that Luke now commandeers a new ship, the Princess Andromeda. Aboard the ship are several hypnotized mortals as well as several monsters and former campers. Near the end of book 2, he duels Percy, the duel is interrupted by Chiron and other centaurs.

The Battle of the Labyrinth
In book 4 Luke only appears in once, in Antalus' stadium, His last name is also learned, "Castellan". After it is revealed that Kronos has taken control of Luke's body, Kronos says that Luke was "...scared of you, Perseus Jackson... [but] I am not..." and that kept him in line. Presently it isn't known whether Luke has died or if he still lives inside Kronos, though in the Battle of the Labyrinth Kronos was shown to revert to the Luke persona in pain. Kronos used Luke's body as a shell for his own reincarnation in ''The Battle of the Labyrinth.