Callisto is a fictional character appearing in American comic books published by Marvel Comics and is associated with the X-Men. She is the leader of New York City's subterranean mutant settlement the Morlocks until losing that post in a duel against Storm. Storm subsequently leaves the group in Callisto's care as her representative, and the two eventually form an uneasy alliance. Callisto appears in the 2006 film, X-Men: The Last Stand, where she is played by actress Dania Ramirez.