Professor Emil Keller has created a machine that can pacify even the most dangerous of criminals. But when the Doctor and Jo arrive at Stangmoor Prison for a demonstration, things start to go horribly wrong - especially when they discover that the Doctor's old enemy the Master is responsible for the machine.
Don Houghton | Writer |
Timothy Combe | Director |
Dudley Simpson | Music |
Terrance Dicks | Script Editor |
Barry Letts | Producer |
Jan Harrison Shell | Makeup Artist |
Roger Harvey | Editor |
Bobi Bartlett | Costume Design |
Sam Upton | Editor |
Eric Monk | Lighting Director |