166 minutes
5/9/1970
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.
Jon Pertwee
as Dr. Who
Caroline John
as Liz Shaw / Section Leader Elizabeth Shaw
Nicholas Courtney
as Brigadier Lethbridge-Stewart / Brigade Leader Lethbridge-Stewart
John Levene
as Sergeant Benton / Platoon Under Leader Benton
Olaf Pooley
as Professor Stahlman / Director Stahlman
Christopher Benjamin
as Sir Keith Gold
Sheila Dunn
as Petra Williams / Dr Petra Williams
Derek Newark
as Greg Sutton
David Simeon
as Private Latimer
Derek Ware
as Private Wyatt
Walter Randall
as Harry Slocum
Ian Fairbairn
as Bromley
Roy Scammell
as RSF Sentry
Keith James
as Patterson
Peter Thompson
as Primord
Philip Ryan
as Primord
Walter Henry
as Primord
Pat Gorman
as Primord
Dave Carter
as Primord
Barry Letts
as Loudspeaker Voice
Derek Martin
as UNIT Soldier
Terry Walsh
as UNIT Soldier
Ian Elliott
as UNIT Soldier
Alan Chuntz
as UNIT Soldier
Alan Clements
as Technician Phillips