The Fifth Doctor, Tegan and Turlough arrive on Sea Base 4, a nuclear warhead station under the sea that has some very nasty neighbours.

Many incarnations of the Doctors and their old companions are taken out of time and deposited in the Death Zone on Gallifrey. There, they must battle the Master, Daleks, Cybermen and Yeti in order to reach the Dark Tower and discover the Tomb of Rassilon.

King Lear, old and tired, divides his kingdom among his daughters, giving great importance to their protestations of love for him. When Cordelia, youngest and most honest, refuses to idly flatter the old man in return for favor, he banishes her and turns for support to his remaining daughters. But Goneril and Regan have no love for him and instead plot to take all his power from him. In a parallel, Lear's loyal courtier Gloucester favors his illegitimate son Edmund after being told lies about his faithful son Edgar. Madness and tragedy befall both ill-starred fathers.

Still trapped in E-Space, the Doctor, Romana, Adric and K9 encounter a medieval civilisation dominated by the Three Who Rule, vampires who govern from their mighty castle.

Jack Regan, an unethical officer of the Flying Squad, uses unorthodox methods to pursue criminals with the help of his partner, George Carter.

The adventures of The Doctor, a time-traveling humanoid alien known as a Time Lord. He explores the universe in his TARDIS, a sentient time-traveling spaceship. Its exterior appears as a blue British police box, which was a common sight in Britain in 1963 when the series first aired. Along with a succession of companions, The Doctor faces a variety of foes while working to save civilizations, help ordinary people, and right many wrongs.

The adventures of The Doctor, a time-traveling humanoid alien known as a Time Lord. He explores the universe in his TARDIS, a sentient time-traveling spaceship. Its exterior appears as a blue British police box, which was a common sight in Britain in 1963 when the series first aired. Along with a succession of companions, The Doctor faces a variety of foes while working to save civilizations, help ordinary people, and right many wrongs.