The Doctor and Sarah encounter Professor Sorenson who plans on transporting anti-matter.

The Doctor and Sarah arrive too late, and a ravenous monster emerges from Zeta Minor.

The Doctor and Sarah continue their efforts to stop the release of deadly anti-matter.

The Doctor realizes not only must he save the universe, but Sorenson, from himself.

Giant wasp-like Wirnn attack the last survivors of Earth, cryogenically preserved inside an automated space station. With Tom Baker.

Aliens scheme to seize the galaxy.

The Doctor must thwart the aliens.

The Kinda is apparently a primitive tribe but three team members have already vanished.

The Doctor makes a final stand against an army of Cybermen in order to protect humans from destruction.

The Doctor looks for Weng-Chiang in an opium den.

The Doctor has his final confrontation with Weng-Chiang.

he Doctor's curiosity is aroused by a darkened remote lighthouse.

An alien stalks survivors.

As the number of victims grows, the Doctor is still at a loss as to the identity of the killer.

The Doctor and Leela are forced into a battle for survival against the alien killer.