DOCTO(R), or the Department of Overt and Covert Tactical Operations (Regional), was an intelligence organisation. Its secret base was located deep beneath Guildford.
DOCTO(R) worked with Lettice Butts and Radcliff in their attempt to recover the Egg of Abundance from Abel Crumpton. When Lettice was captured, Harry Sullivan was recruited to help.
Emily Dunkirk briefed Harry on his mission and gave him a transmitter and a watch. (The Man from DOCTO(R)