Sir John Sudbury
Sir John Sudbury was head of department C-19 from the late 1960s until 1992. Before and during this time, Sir John was a Junior defence minister under successive governments, as part of a long and distinguished political career which is all on public record. It is rather unusual for an MP to hold such an office under governments from different parties. Perhaps his excessive inside knowledge of defence affairs, and his parliamentary safe seat of Woodhaven helped him there.
Despite being head of the department, there was much of C-19's darker side that Sir John didn't know about until the Cheviot Hills Shutdown in 1970 (at least according to some leaked documentation about a purge of C-19 soon after this incident. Around this time, certain members of C-19 attempted to assassinate him, although their failed attempt was publicly interpreted as an attempt to kill the Prime Minister, who was standing next to him at the time. Sudbury also provided authorisation for the Youthful Doctor during the Heathrow Incident. Sir John retired from the Commons in 1992 and took up a seat in the House of Lords, which he still holds today.