Sam Worthington as Perseus Liam Neeson as Zeus Ralph Fiennes as Hades Gemma Arterton as Io Jason Flemyng as King Acrisius \ Calibos Alexa Davalos as Princess Andromeda Mads Mikkelsen as Draco Liam Cunningham as Solon Nicholas Hoult as Eusebios Hans Matheson as Ixas Rory McCann as Belo Luke Evans as Apollo Danny Huston as Poseidon Alexander Siddig as Hermes Agyness Deyn as Aphrodite Pete Postlethwaite as Spyros Elizabeth McGovern as Marmara Luke Treadaway as Prokopion Polly Walker as Cassiopeia Vincent Regan as Cepheus Kaya Scodelario as Peshet William Houston as Ammon Ian Whyte as Sheikh Sulieman
who played io in clash of the titans
Gemma Arterton