Episode Four
Series Episode Number: 327World Premiere: Sat 10 Jun 1972 - 5:50pm BST [BBC One] (United Kingdom)
Running Time: 23 minutes 55 seconds
7.60 Million (UK)
Chart Position: 28 () (UK)
Recorded on Wed 10 May 1972 in TC4
Archive State: RSC conver
As UNIT forces approach, the Master leaves for Atlantis in his TARDIS. However, the Doctor is not far behind and in the time vortex, the two Time Lords confront each other.