UNIT is providing security cover at an experimental drilling project at Eastchester, designed to penetrate the Earth's crust and release a previously untapped source of energy. Soon, however, the drill head starts to leak an oily green liquid that transforms those who touch it into vicious primeval creatures with a craving for heat. The Doctor is accidentally transported "sideways in time" by the partially repaired TARDIS control console into a parallel universe where the drilling project is at a more advanced stage. Thwarted by his friends' ruthless alter egos, he works to save both universes.

• DirectorDouglas Camfield
• Release9 May 1970
• Genre
  Science Fiction / TV Movie
• Duration2h 46m
• Budget?
• Revenue?
• Rate
  

  8.8
  4 reviews
• Productions

  BBC