The TARDIS lands on Phobos, moon of Mars - where extreme sports nuts of the future indulge their passion for gravity-boarding and wormhole-jumping. But there's something lurking in the shadows, something infinitely old and infinitely dangerous. It's not for nothing that 'Phobos' is the ancient word for 'fear'...
Written By: Eddie Robson
Directed By: Barnaby Edwards
Paul McGann (The Doctor); Sheridan Smith (Lucie Miller); Katarina Olsson (Headhunter/Amy); Timothy West (Kai Tobias); Nerys Hughes (Eris); Ben Silverstone (Drew); John Schwab (Hayd); Tim Sutton (Farl)