6.6 334 The TARDIS is drawn by a mysterious force and lands on the alien planet Vortis. There the Doctor, Ian, Barbara and Vicki find themselves caught up in a war between an evil force known as "The Animus", its ant-like Zarbi allies, and the butterfly-like Menoptra race and their allies the subterranean Optera.
Runtime: 24 min
Starts: William Hartnell, William Russell, Jacqueline Hill, Maureen O'Brien
Director: Richard Martin