29 January 1977
Russell Hunter (Uvanov), Pamela Salem (Toos), David Bailie (Dask), David Collings (Poul), Brian Croucher (Borg) [1-2], Tania Rogers (Zilda) [1-2]*, Tariq Yunus (Cass) [1-2], Rob Edwards (Chub)  Gregory de Ponlay (D.84), Miles Fothergill (S.V.7); Mark Blackwell Baker, John Bleasdale, Mark Cooper, Peter Langtry, Jeremy Ranchev, Richard Seager (Robots).
|Written by||Chris Boucher|
|Directed by||Michael Briant|
|Produced by||Philip Hinchcliffe|
On a distant, barren planet, Storm Mine 4 trawls across bleak deserts and through fierce duststorms in search of rare and valuable metals. On board the Sandminer is a small skeleton crew, who alternate between indulgentrelaxation and skilled mining work. The mundane, day-to-day duties of the mine are attended to by a much larger complement of servile robots. This is a society that is dependant on robots for all areas of life, the people comforted by the knowledge that the strictest safeguards are built into each and every robot’s programming. So when one of the miner crew is murdered, suspicion falls on two new arrivals…
The Doctor and Leela arrive on board, and are immediately accused of being the prime murder suspects. But The Doctor soon realises that perhaps the killer isn’t human. More deaths occur — can he persuade the remaining crewmembers that the killer may be a robot?