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.
William Hartnell
Jacqueline Hill
William Russell
Maureen O'Brien
Catherine Fleming
Score: 7.6
Score: 6.5
Score: 6.4
Score: 8.3
Score: 7.5
Score: 7.8
Score: 7.7
Score: 5.3
