When the TARDIS lands in the swamp lands, the monstrous Kroll, who swallowed the fifth segment centuries before, rises from the depths. In order to revert Kroll to its natural form, the Doctor must get the key tracer near him before it's too late.

The inhabitants of a crashed Starliner are being terrorised by a race of Marshmen on Alzarius.

The Doctor, Romana, K9 and Adric - an Outler from Alzarius who has stowed away aboard the TARDIS - arrive on a planet where the native villagers live in fear of 'the Wasting' and of three Lords named Zargo, Camilla and Aukon who rule from an imposing Tower. The Lords are soon revealed to be vampire servants of the last of the Great Vampires, a race referred to in Time Lord mythology.

A sinister surprise awaits the Doctor.

Some of Ace's friends have been transported to another planet where they are hunted by the Cheetah People.

The Doctor meets a strange man in Victorian England called The Doctor.

The Doctor plans to show Rose the London Olympics in 2012; a mother hides her daughter's unearthly powers.

The human race rejoices as ghosts of loved ones return home; an invasion force threatens modern day Earth.

Two mighty armies wage war across the Earth; terror emerges from beneath Torchwood Tower; the Doctor faces a dilemma.

The Doctor discovers an Ice warrior plot to weaken the Earth's resistance.