Back up to: Doctor Who
4/4 As the Selachians' grip tightens on Moon base, the Time Lord reveals his true purpose.
3/4 The Selachians appear to be in control of the Moon, but who is behind their success?
2/4 Dr Klein recruits her reluctant prisoner to help fight the invading Selachians.
1/4 A time traveller arrives at a Moon base to save the Earth, but it's not who you think.