Ep 26. Logopolis: Part 2

The Classic Doctor Who season 18 episode 26 is titled "Logopolis: Part 2." This episode is the second part of a two-part arc, which begins with "Logopolis: Part 1". The episode was written by Christopher H. Bidmead and directed by Peter Grimwade. The episode was originally aired on March 21, 1981.

In the previous episode, the Fourth Doctor (played by Tom Baker) and his companions Tegan (played by Janet Fielding) and Adric (played by Matthew Waterhouse) arrived on the planet Logopolis, where they discovered that the Master (played by Anthony Ainley) was attempting to use the planet's advanced mathematical abilities to create a new universe under his control. The Doctor enlisted the help of the Logopolitans to stop the Master's plan, but in doing so, he inadvertently caused the collapse of the universe.

In "Logopolis: Part 2," the Doctor and his companions must race against time to prevent the end of the universe. To do so, they must find a way to enter the Master's TARDIS and stop him from carrying out his plan. Meanwhile, the Doctor begins to feel the effects of his prolonged exposure to the Logopolitan calculations and realizes that he is dying.

As the Doctor and the Master engage in a final showdown, Adric confronts the reality of the Doctor's impending death and must come to terms with the end of his time with the Doctor. Tegan, meanwhile, is still reeling from the shock of her friend's sudden transformation into a new and unfamiliar incarnation of the Doctor.

The stakes are high as the Doctor faces his greatest challenge yet, with the fate of the universe hanging in the balance. Will he be able to save the day and defeat the Master, or is the end of everything truly at hand? Find out in "Logopolis: Part 2".