From TARDIS Index File, the free Doctor Who reference.
The Controller was a man who existed in an alternate 22nd century England, he was 'Controller' over the peoples of a section of England, a role that his family had been part of for at least a generation. He was answerabled to, and worked for the Daleks. He encountered Jo Grant after she used a time machine to travel from the 20th century to the 22nd, and then in turn met the Doctor. After conversing with them for sometime he allowed them to escape from the compound the stop the Daleks from altering time in the 20th century, he was exterminated by the Daleks. (DW: Day of the Daleks)
