Hall of Mirrors (short story)

Summary
The TARDIS has an unexpected power failure and makes a landing in an endless corridor of mirrors. The Doctor and Peri are surprised to find the apparently disconnected chameleon circuit engaged. The TARDIS transforms into one of the many mirrors. Peri marks it with her lipstick. The Doctor hears voices up ahead and they work their way through the maze of mirrors to a large, empty hall with a single mirror.

At a table in the middle of the room sits two similar people who each gives their name as Ademus. The Doctor knows the name but can't remember anything else. Ademus explains that, like them, he was a traveller who has been trapped. The only way to escape and free the TARDIS is to smash the mirror, but he refuses to reveal why he can't. Finding his way back to the TARDIS, the Doctor returns with a U.H.L.F. (a large sonic lance that he once picked up on Mars). He switches it on and points it at the mirror, which shimmers and warps - he suddenly stops.

The Doctor tells Ademus that he needs something else from the TARDIS, but Ademus is not happy. The Doctor takes Peri with him. He explains who Ademus was - a dangerous man with tremendous powers. The White Guardian, stopped him and handed him back to his people. They imprisoned Ademus in a world of his own mind, one given substance by a mental projection controlled by a semi-sentient machine behind the mirror. They are trapped. They can't leave without breaking the machine and if they do, they will be trapped forever in the manifestation of Ademus' mind.

Using the last reserves of power in the TARDIS the Doctor flies it to the mirror where Ademus waits. The Doctor announces he has a means of freeing the TARDIS, yet leaving Ademus imprisoned. He produces a sphere that when wired up will absorb the power from the mirror and channel it back to the TARDIS.

Before the sphere is connected, Ademus' fury is revealed. He changes the reality of his world. Fighting his way through rain, wind, storms and yawning crevasses, the Doctor connects the device. The Doctor hears Ademus' begging not to be left alone with himself, but leaves with Peri in the TARDIS. Ademus is left behind, trapped in the physical manifestation of his schizophrenia and and the mirrors, which reflect his sense of loss and confusion.

Characters

 * Sixth Doctor
 * Peri
 * Ademus

Continuity

 * According to the Doctor, the TARDIS' chameleon circuit has been disconnected, presumably after the unsuccessful attempts to repair it in Logopolis and more recently at the time of Attack of the Cybermen.
 * The Doctor opens the TARDIS doors manually when the TARDIS is all but drained of its power. This was done in Planet of the Daleks.