Clent
Clent was the leader of Brittanicus Base in 5000. He helped the Second Doctor defeat the Ice Warriors.
Clent was very reliant on the base's computers. He didn't approve of independent thinking and had a falling out with scientist Elric Penley. Clent was a good organiser and had succeeded in every project he had worked on prior to serving at Brittanicus Base.
When the Doctor arrived at the base during an emergency, Clent soon came to rely on him for help despite the Doctor's disdain for the computers. Clent was faced with a dilemma at the arrival of the Ice Warriors: use the ioniser to keep the glaciers at bay and risk the ioniser destroying the Ice Warrior ship and everything around it, or not use the ioniser and let the base be destroyed by the glaciers. He tried to get answers from the computer but didn't have all the information he needed.
He sent Arden and Jamie McCrimmon to spy out the Ice Warrior ship to learn its propulsion system. When they were attacked by Ice Warriors, Clent had to send the Doctor on the same mission. When the Ice Warriors invaded the control room, he and Miss Garrett tried to convince Varga that they couldn't shut down the ioniser, but gave in when he threatened to kill them. In the end he had to let Penley override the computer to use the ioniser on the glacier, which also destroyed the Ice Warrior ship. (TV: The Ice Warriors)
