WOTAN is the most advanced artificial intelligence of it's time, acting as the main antagonist of the Doctor Who episode The War Machines. It also serves as the posthumous antagonist of the novel The Time Travellers, and the main antagonist of the Big Finish audio spin-off Torchwood One: Machines.
He was voiced in The War Machines by Gerald Taylor, and by Nicholas Pegg in Machines, with both having served as Dalek operators.
History
WOTAN was built in the mid 1960s by a team led by Professor Brett, said to be a decade ahead of it's time. Housed in the Post Office Tower in London, it was intended that WOTAN would be linked up to, and subsequently take control of, other prominent computers in organisations all over the world - including Parliament, the White House, the Free Trade Association, Cape Kennedy and the Royal Navy -, on a day designated ‘C-Day’. Highly intelligent, WOTAN was so brilliant that that it somehow even knew what ‘TARDIS’ stood for, and, according to Professor Brett, never made mistakes.
However, WOTAN came to the belief that humanity and indeed all organic life was inefficient, and the world would be better with WOTAN in charge. It was able to transmit a hypnotic signal through phone lines, and ordered the construction of mobile, armed computers which were designated War Machines. These were constructed in locations across London, and were to be used to conquer capitals all over the world.
The War Machines
WOTAN believed that only the First Doctor, whom he believed was a human called Dr. Who, could be a genuine threat. To this end, it brought his ‘secretary’ Dodo under its control, along with other humans such as its creator, Professor Brett, his assistant, Professor Krimpton, the head of security, Major Green and his secretary Polly, but when it attempted to hypnotise The Doctor over a telephone line, The Doctor not only resisted the attempt, but discovered what had happened to Dodo and was able to free her from its control. Aided by Sir Charles Summer, a government official in charge of the WOTAN project, and the sailor Ben Jackson, The Doctor managed to immobilise one of the War Machines by prompting WOTAN’s servants to release it before it was fully programmed, and later managed to capture and reprogram another War Machine using electronic cables to block it from WOTAN’s signals. Having reprogrammed the captured War Machine, The Doctor sent it to destroy WOTAN's central processor, the War Machines all simultaneously shutting down and those under WOTAN’s control being freed with the supercomputer’s destruction.
The Time Travellers
Multiple timelines branched off from these events. In the original timeline where the Doctor was not involved, WOTAN's invasion was successful, being able to take control of people's minds via radio transmissions, but it was eventually destroyed in 1969. Civilization was devastated, however. WOTAN's legacy was years of warfare that left many nations as brutal, impoverished dictatorships; millions of people were left brain-damaged by WOTAN's former control of their minds and radios and telephones were outlawed by nations like the United Kingdom. An earlier version of the First Doctor became aware of this when he arrived there in 2006.
Torchwood One: Machines
to be added