A burned-out British police detective finally snaps while interrogating a suspected child molester.

Delger, "the man who gets things done", finds himself involved in London's vice world, in between sleeping with his two neighbours Elaine and Wendy, a masseuse who "can't give a man a massage without turning him on".

In the 26th century, the Doctor and Jo uncover a plot by the Master to provoke an interplanetary war between Earth and Draconia.

The Third Doctor and Sarah arrive in 1970s London to find it has been evacuated because dinosaurs have appeared mysteriously. It turns out the dinosaurs are being brought to London via a time machine to further a plan to revert London to a pre-technological level.

The newly-regenerated Doctor helps UNIT battle a sentient robot being manipulated by a corrupt scientific organization.