The Daleks prepare to launch a deadly plague missile that will kill everyone on Exillon.
Doctor Who | Death to the Daleks (Serial)
Death to the Daleks: Part 3

The Daleks force the Exillons to work as slave labor to mine the life-saving parrinium.
Death to the Daleks: Part 2

Dalek weapons are useless due to the power drain so they make a truce with the Doctor.
Death to the Daleks: Part 1

The TARDIS suffers a power drain and is forced down on the planet Exxilon.