On the planet Vortis, the Doctor and his companions aid the butterfly-like Menoptra in their battle against the parasitic Animus and its mind-controlled minions, the ant-like Zarbi.
The Doctor
Barbara Wright
Ian Chesterton
Vicki
Animus (voice)
Vrestin
Hrostar
Hrhoonda
Hlynia
Hillo
Hetra
Nemini
Zarbi
Director
Sound
Makeup Artist
Costume Design
Editor
Choreographer
Camera Operator
Lighting Director
Writer
Producer
Script Editor
Music