Serial: XXX  Episode Nos. 366, 367, 368, and 369.  Title: Death to the Daleks

The power supply for a party of humans and for the TARDIS is being drained by a strange alien city on the planet Exxilon.  All those found near it are put to death by the natives, that is until a party of Daleks arrive on the planet.  Both the humans and the Daleks require a precious mineral from the planet to cure a space plague, and although the power loss has forced them into an uneasy alliance, the Doctor knows that the Daleks will stop at nothing to prevent the Earth mission ship from succeeding....

starring Jon Pertwee as Doctor Who and Elisabeth Sladen as Sarah Jane Smith. Written by Terry Nation, Produced by Barry Letts, and Directed by Michael Briant.

Originally transmitted from 23 February 1974 to 16 March 1974 on BBC1.