The TARDIS lands on the jungle world of Spiridon and Jo tends to the injured Doctor. Unbeknownst to both of them, they have landed in the middle of a war that The Doctor himself helped reignite.

This week Paddy and Tricia watch as The Doctor is reunited with the descendants of the Thals he helped liberate. Together with Jo he helps them carry out a mission on the hostile world which has now become a Planet of the Daleks.