Part Four
Series Episode Number: 557World Premiere: Tue 12 Jan 1982 - 7:05pm GMT [BBC One: Not Wales] (United Kingdom)
First Broadcast: Thu 9 Apr 2015 - 8:30pm EDT [Retro TV]
Running Time: 24 minutes 12 seconds
10.40 Million (UK)
Chart Position: 46 () (UK)
Recorded on Wed 30 Sep 1981 in Television Centre 3
As recursive occlusion threatens to destroy everything and everyone in Castrovalva, the Master's space/time trap is revealed, with Adric at its heart...