The Doctor walked slowly forward into the cul-de-sac. The giant dinosaur turned its head to focus on the midget now approaching...The Doctor aimed his gun to fire...suddenly from behind came a great roar of anger. He spun round, blocking the exit from the narrow street towered a Tyrannosaurus Rex, its savage jaws dripping with blood.
The Doctor and Sarah arrive back in the TARDIS to find London completely deserted: except for the dinosaurs. Has the return of these prehistoric creatures been deliberately planned and, if so, who can be behind it all?