Carol Bell

Captain Caroline "Carol" Bell was a UNIT officer. She was a member of the Brigadier's personal support staff.

Prior to her enlistment in UNIT, while a lance corporal, she served as Colonel Lethbridge-Stewart's assistant at the London Regiment offices in Battersea during the clean-up after the London Event. (PROSE: The Forgotten Son) She was promoted to Corporal at some point between that and the formation of UNIT, where she became one of the initial members of the Brigadier's personal staff. (PROSE: The Scales of Injustice)

Bell performed surveillance at the town of Smallmarshes, where she saw a stealth aircraft land. She reported in to HQ that the Third Doctor, a Silurian, the missing boy Marc Marshall, and Sergeant Mike Yates had been taken aboard this craft. (PROSE: The Scales of Injustice)

Bell informed the Brigadier that Captain Chin Lee was on the phone. The Brigadier later told her to check exactly what time the phone call was made. When the Thunderbolt was stolen, the Brigadier told her to have a helicopter standing by for him, along with a mobile HQ and a full forensic team. (TV: The Mind of Evil)

She seemed to be on good terms with Jo Grant, having a fondness for telling dirty jokes, (PROSE: Where the Heart Is) and Yates often spent evenings with her. (AUDIO: The Screaming Skull)

She was blackmailed by survivors of Inferno Earth into betraying UNIT when they kidnapped her brother and threatened to kill him unless she did as she was told. (PROSE: The Face of the Enemy) There seemed to be no long-term consequences to her actions, as she was eventually promoted to Sergeant (PROSE: Speed of Flight) and later Captain. (PROSE: The Left-Handed Hummingbird)

She left UNIT in 1979 for a business career. (PROSE: Interference - Book Two) By 1989, Bell was married, and had one child. (PROSE: Business Unusual)

At some point after leaving UNIT, she was in a car accident that left her with brain damage. (PROSE: The Left-Handed Hummingbird)

By the mid 2000's she had passed away. (PROSE: Faithful Friends: Part 3)

Behind the scenes
Corporal Bell's first name Carol is revealed in The Scales of Injustice. Her full first name is Caroline, as revealed in The Forgotten Son, although she more often went by Carol.