In a Mars base, the inhabitants are being infected by a mysterious water creature which takes over its victims. The Doctor is thrust into the middle of this catastrophe, knowing a larger one is waiting around the corner.

Cast:David Tennant, Lindsay Duncan, Peter O'Brien, Sharon Duncan-Brewster, Gemma Chan, Aleksandar Mikic,

Genre:Horror, Science Fiction, Drama, Mystery, Adventure, TV Movie,

country:United Kingdom,

Production:BBC Cymru Wales,