The Doctor and UNIT investigate a deadly infection lurking underneath the Welsh mining town of Llanfairfach. It's an adventure that will change Jo Grant's life forever...
The Doctor
Jo Grant
Brigadier Lethbridge-Stewart
Sergeant Benton
Captain Mike Yates
Cliff Jones
Stevens
Elgin
Hinks
Bert
Hughes
Fell
Minister of Ecology
June 23, 1973
The Doctor
Jo Grant
Brigadier Lethbridge-Stewart
Sergeant Benton
Captain Mike Yates
Cliff Jones
Stevens
Elgin
Hinks
Bert
Hughes
Fell
Minister of Ecology
