He was voiced by Francis Matthews.
Paul Metcalfe was born in Winchester on December 17, 2036 to a family with a long military history, he graduated from Winchester University in 2057, at the age of 21, and then went to West Point Military University; he later transferred to the World Army/Air Force, where within 2 years, he became the youngest colonel the WAAF had known to date.
- Main article: Captain Scarlet's Missions
- Like most Mysteron copies, his original body was destroyed and then retrometabolised to a Mysteron agent. However, unlike most Mysteron agents, Captain Scarlet retains his original memories and personality, whilst retaining all powers of Mysteron copies, including:
Also, at least for the first few episodes, Captain Scarlet would become nauseous in the presence of another Mysteron agent; this ability mysteriously disappeared soon after.
- Captain Scarlet's puppet was later reused for bumbling agent Paul Blake, in the television series The Secret Service.