The final episode saw the departure of Patrick Troughton as the Second Doctor and Frazer Hines and Wendy Padbury as companions Jamie McCrimmon and Zoe Heriot. It was the first time in the history of Doctor Who that either a companion or an incarnation of the Doctor made their last regular appearance in the concluding episode of a season. It was also the first time that an incarnation of the Doctor and all his companions were written out of the program in the same story.