Little is known of John Benton's background before joining U.N.I.T. In 1968, Benton was a private in the army but was promoted to Corporal on the recommendation of Major-General Rutlidge (Rutlidge died during the collapse of I.E.) and became part of the original UNIT UK staff. He served as a corporal until UNIT's involvement with the collapse of I.E., after which he was promoted to Sergeant. He was a Sergeant from 1970 to 1975 when, following the retirement of Captain Mike Yates he was promoted to RSM. He served as RSM from the Think Tank scandal.
Benton stayed with UNIT until 1979, when he retired and went into the used car business, although he later returned to work for UNIT in a desk-bound role. During his time in UNIT, Benton was party to most of UNIT's big operations and was the officer most often involved in active duty on these operations. His role involved a lot of contact with the UNIT Doctor, as well as a lot of contact with the various things that UNIT has covered up. Although little is actually known about him, he was one of UNIT's founding members, and one of its key field agents during the most active period in its history and party to UNIT's greatest secrets and worthy of mention here.