Thor Freudenthal Director Logan Lerman Percy Jackson Actor Brandon T. Jackson Grover Actor Alexandra Daddario Annabeth Chase Actor Jake Abel Luke Castellan Actor Douglas Smith Tyson Actor Leven Rambin Clarisse Actor Nathan Fillion Hermes Actor Anthony Head Chiron Actor Stanley Tucci Mr. D Actor Mary Birdsong Gray Sister 1 Actor Yvette Nicole Brown Gray Sister 2 Actor Missi Pyle Gray Sister 3 Actor Connor Dunn Tereus Actor Paloma Kwiatkowski Thalia Actor Christopher Redman Reardon Actor Robert Knepper Kronos Actor Richard Yearwood Ganymede Actor Ron Perlman Polyphemus Voice Shohreh Aghdashloo Oracle Voice Octavia Spencer Martha Voice Craig Robinson George Voice Marc Guggenheim Screenwriter Karen Rosenfelt Producer Michael Barnathan Producer Chris Columbus Executive Producer Mark Radcliffe Executive Producer Mark Morgan Executive Producer Guy Oseary Executive Producer Greg Mooradian Executive Producer Shelly Johnson Cinematographer Mark Goldblatt Film Editing Andrew Lockington Original Music Claude Paré Production Design Helen Jarvis Supervising Art Direction Dan Hermansen Art Director Kirsten Franson Art Director Shane Vieau Set Decoration Monique Prudhomme Costume Design Alyssa Weisberg Casting Coreen Mayrs Casting Heike Brandstatter Casting