User blog comment:Menara/The Son of Sobek: The official PJ and Kane Chronicles Crossover/@comment-10364601-20130603035511/@comment-3146930-20130603040657

So Carter is looking for this croc; ends up getting eaten. Percy saves him, but the croc gets away. Percy and Carter get into a fight. They call a truce and go after the croc. Carter and Percy show off their awesome powers. The croc is defeated. Carter and Percy feel like someone is trying to cause trouble by bringing them together. Carter takes the croc and the magic necklace, but places a spell on Percy's hand so if Percy ever needs him, all he needs to do is say "Carter" and Carter can find him.

Pretty much all you need to know.