Part OneSeries Episode Number: 436
World Premiere: Sat 30 Oct 1976 - 6:09pm GMT [BBC One] (United Kingdom)
First Broadcast: Thu 15 May 1980 - 5:30pm CDT [WTTW 11 Chicago]
Running Time: 21 minutes 13 seconds
11.80 Million (UK)
Chart Position: 15 () (UK)
Recorded on Tue 07 Sep 1976 in TC3
The Doctor answers a summons to return home to Gallifrey and races to prevent a tragedy as the outgoing Time Lord president prepares to announce his successor.