Part FourSeries Episode Number: 591
World Premiere: Wed 9 Feb 1983 - 6:47pm GMT [BBC One] (United Kingdom)
First Broadcast: Thu 30 Apr 2015 - 8:30pm EDT [Retro TV]
Running Time: 24 minutes 33 seconds
7.70 Million (UK)Appreciation Index: 68 (UK)
Chart Position: 78 () (UK)
As the Doctor's ethics are challenged and the two Brigadiers finally meet, Turlough plots with the Black Guardian to bring the Time Lord down once and for all...