Black Guardian

The Black Guardian is a character in the long-running British science fiction television series Doctor Who. He was played by Valentine Dyall.

The Black Guardian is an anthropomorphic personification of the forces of entropy and chaos, the counterpart of the White Guardian, a personification of order. The two Guardians balance out the forces in the universe, although the Black Guardian seems to desire to upset the balance in favour of chaos and evil while the White Guardian prefers to maintain the status quo. The Guardians both appeared in Season 16 of the programme, where all six serials of that season were linked together in the quest for the Key to Time, an artifact of immense power that would give the wielder supreme power over all existence.

Overview
The White Guardian gave the Fourth Doctor the task of finding the scattered six segments of the Key at the beginning of The Ribos Operation. Once the Doctor had assembled the Key, the Black Guardian disguised himself as the White and attempted to trick the Doctor into handing it over. The Doctor saw through the deception after the Guardian appeared indifferent to the fact that the sixth segment — Princess Astra of Atrios — had ceased her independent existence by becoming part of the Key. The Doctor then dispersed the Key, earning the Black Guardian's eternal enmity and forcing the Doctor, for a period, to attach a randomiser to his TARDIS to avoid being tracked through time and space.

He briefly appears at the end of Logopolis, in the montage of past enemies taunting the Doctor. The next appearance of the Black Guardian was in the 1983 serial Mawdryn Undead, the first of three linked serials known as the Black Guardian Trilogy. He enlisted a young public school student named Vislor Turlough, offering the young man (who was really an alien exiled on Earth) passage home if he killed the Doctor (then in his fifth incarnation), and death if he failed. Turlough joined the TARDIS crew, struggling with the dilemma and eventually chose loyalty to the Doctor in Enlightenment, the last serial of the trilogy. Although extremely powerful, the Guardians apparently cannot be seen to act directly, which is why they can only affect things through agents such as Turlough and the Doctor. Other agents of the Black Guardian include Cessair of Diplos in The Stones of Blood, The Shadow in The Armageddon Factor and Captain Wrack in Enlightenment.

Turlough's choice and the use of the Enlightenment crystal apparently banished the Black Guardian – he is seen to burst into flames and appear in negative again, before disappearing. The White Guardian warned, though, that he would return – angrier now that the Doctor had thwarted him twice. However, the character has yet to make a return appearance in the television series.

Other appearances
The Black Guardian features in the Virgin Missing Adventures spin-off novel The Well-Mannered War, by Gareth Roberts. In that story, the Black Guardian catches up with the Fourth Doctor and Romana following the loss of the Randomiser, trapping them in a situation where they must either remain in the TARDIS and the Time Vortex for all eternity or release a powerful telepathic insect hive on 26th-century Earth, and they are forced to leave the known universe as a consequence. It is of course possible that the Doctor was later able to return to our universe.

The Black Guardian resurfaced again in Paul Cornell's short story "Time and Time Again", published in an issue of Doctor Who Magazine commemorating the 30th anniversary of the Doctor Who television programme. In the story, the Black Guardian punishes the Doctor's defiance by altering history so that the Doctor never left Gallifrey. In the revised timeline, the Doctor never visited Earth, and the planet's vulnerability has resulted in repeated alien invasions. The White Guardian commissions the Doctor, Benny, and Ace to journey across the Doctor's own timestream to once again assemble the Key to Time, the fragments of which are disguised as artifacts from the Doctor's past in the possession of each of his past incarnations.

In the BBC Books spin-off novel The Quantum Archangel by Craig Hinton, the Black Guardian appears briefly with the White Guardian and four others, who form a Council of Guardians that oversee reality. The other four Guardians were first mentioned in Divided Loyalties by Gary Russell, which states that one of them is the Celestial Toymaker.

The Black Guardian returns in the final moments of the Big Finish audio drama The Judgement of Isskar, and reappears in the proceeding two stories - The Destroyer of Delights and The Chaos Pool. Once again, The Key to Time is being sought, but this time with the Fifth Doctor. In these plays, The Black Guardian is played by David Troughton. He is portrayed as losing his powers due to the Key decaying, forcing him and the White Guardian to operate on a lower level of existence.