One Fob Watch that is well know to all Doctor Who fans is the Fob Watch that, when used with a Chameleon Arch, will turn a Time Lord into a different species.
There have been three notable uses of the Fob Watch, (Human Nature/ Family of Blood and Utopia), however Human Nature and Family of Blood were a two part episode, and Utopia was the start of a three part episode.
It is suggested that the process of removing the Time Lord essence is extremely painful, as each and every cell must be re-written into the chosen species, usually human.
Appearances (Official BBC/Big Finish Media)[]
A fob watch exterior for the Chameleon Arch has appeared in five episodes of the BBC Doctor Who television series (Human Nature/ Family of Blood, Utopia, Survivors of the Flux and The Vanquishers).
In the Human Nature Arc, The Doctor turns himself into a human to escape a family of aliens who believe that by swallowing his essence (The Family of Blood), they will live forever. It fails.
In Utopia, the human Professor Yana was revealed to be The Master who had used the Chameleon Arch to rewrite his cellular makeup to become human and flee The Last Great Time War. This was expanded upon in the Big Finish audio drama, The Heavenly Paradigm, when the Master inadvertently altered the timeline so that the Daleks had taken control of the Cruciform instead of losing to the Time Lords in the battle for control. Horrified at what he had done, and proclaimed the Time War lost, he used the Chameleon Arch to remove his Time Lord DNA and become human, regressing his body to an infant.
The Chameleon Arch has also appeared in different forms, such as a locket (One Life (Big Finish audio)), or a fire alarm (Fugitive of the Judoon).
The Fob Watch
Appearances (Fan Film/Audio)[]
In the Hypertrain Media series Mastermind, the Master keeps a similar pocket watch with him. This watch is of a different design, and doubles as a Tissue Compression Eliminator.