Leela and Lowe take the Doctor to the Bi-Al Foundation for help. But how can they cure an infection of the mind?
Quest roles:
Michael Sheard(Laurence Scarman), Brian Grellis(Safran), Frederick Jaeger(Professor Marius), Roy Herrick(Parsons), Elizabeth Norman(Marius' Nurse), Nell Curran(Reception Nurse), Jim McManus(Opthalmologist), Roderick Smith(Cruikshank), Kenneth Waller(Hedges)