The Doctor and Winser begin to analyse axonite while Chinn plots to secure its use exclusively for Britain.
Quest roles:
Richard Franklin(Mike Yates), Nicholas Courtney(Brig. Lethbridge-Stewart), Bernard Holley(Peter Haydon), John Levene(Sergeant Benton), David Savile(Winser), Roger Delgado(The Master), Paul Grist(Filer), Donald Hewlett(Hardiman), Patricia Gordino(Axon Woman), Tim Pigott-Smith(Marco), Michael Walker(Miseus), Peter Bathurst(Chinn), David March(2nd Radar Operator)