Sergeant Markham was a police officer in Oxfordshire during the 1920s. He was under the command of Sir Robert Muir. After Muir arrested the Fifth Doctor on suspicion of murder on 11 June 1925, Markham was ordered to convey him to the station. Before the arrest was accomplished, however, the Doctor exonerated himself by allowing Muir, Markham and Cummings to enter his TARDIS. (TV: Black Orchid)
