Faction Paradox

Faction Paradox is a fictional time travelling cult/rebel group/organized crime syndicate, originally created by the author Lawrence Miles. The Faction's belief-system as portrayed has some similarities to voodoo, and is sometimes described as such. The family/organization were originally featured as recurring antagonists in the BBC Doctor Who Eighth Doctor Adventures novels, but have since featured in their own continuing tales.

The Faction Paradox universe is centered on the "War in Heaven", a history-spanning conflict between the "Great Houses" and the "Enemy". Originally a subplot in the Eighth Doctor Adventures, the War features characters and concepts evolved from the original Doctor Who set-up, in several cases with names changed or obscured for reasons literary (most of the groups or items mentioned are described in rather different terms with a different emphasis on certain aspects) and legal (the Faction and The Enemy are Miles's creations, but other elements are not — thus the Great Houses are the new series' equivalent to Doctor Who's Time Lords). Faction Paradox themselves are not the Enemy, and play a relatively small, neutral part in the War, willing to act against both sides in their own interests. Lawrence Miles has described them as "a ritualistic time-travelling guerrilla organisation".

The semi-mythical founder of Faction Paradox is Grandfather Paradox, named after the grandfather paradox of time travel theory. Originally a member of the Great Houses himself, the Grandfather created a new group after he became frustrated with the ways of the Great Houses. Faction Paradox therefore takes a good deal of pleasure in irritating the Great Houses, and many of their traditions and rituals are aligned in direct opposition to the way the Great Houses do things. Their time machines are bigger on the inside, in much the same way as TARDISes are, and the titles its members use such as 'Cousin' reference family units which the Great Houses have lost since they became sterile. In the BBC novel The Ancestor Cell, it is indicated that Grandfather Paradox may be an alternate future form of the Doctor. This BBC-only version of the Grandfather is followed up in The Gallifrey Chronicles by Lance Parkin which states that Grandfather Paradox is everyone's possible future self, and according to Gallifreyan myth, he was a Time Lord who acted out the grandfather paradox.

...
Wikipedia