Phobos Starring Paul McGann
The Doctor and Lucie land on Phobos, the moon of Mars, which has become popular with extreme sports fans in the future, due to a wormhole on the surface which is used for bungee jumping. The Doctor and Lucie listen to Kai Tobias's stories of monsters on the surface, although no-one takes him seriously. Later the monsters from Tobias's stories appear and begin attacking visitors. When The Doctor discovers that the monsters are just robots, Tobias reveals that an entity from another universe is in the wormhole and that it feeds on the pleasurable fear extreme sports fans feel. However, it is hurt by real fear and Tobias made the robots to create real fear. The Doctor enters the wormhole and shows the entity his fears, which kill it, and The Doctor and Lucie leave. The Headhunter awakens on the moon's medical ward, angry that she has missed Lucie again.