Professor Kyle was a human geologist from Earth. She was the only survivor after the rest of her expedition was wiped out by the Cybermen's androids in 2526. After escaping from the cave, she alerted the authorities, who ordered a squad of troops to search for bodies. When Scott and his troops arrived to search the caves, Kyle volunteered to go with them.
A short while later, Walters found the Fifth Doctor was there, leading Kyle to speculate that he had killed her crew. When they found him, Kyle found her assistant's coat with a slimy residue on it. The Doctor realised these were the assistant's remains.
The Doctor and his three companions took Kyle to the TARDIS. After the Doctor and Adric had deactivated the Cyber-bomb, Scott and Kyle insisted on accompanying the Doctor to find the source of the attack.
The Doctor and Adric went to investigate Captain Briggs' freighter. Everyone else stayed in the TARDIS. Kyle remained behind on the TARDIS with Nyssa while the others went to search for the Doctor. They were attacked by two Cybermen, who forced their way into the TARDIS. Kyle tried to protect Nyssa by grabbing a fallen Cyber-gun, but before she could fire, the Cyberman shot her in the chest, killing her instantly. (TV: Earthshock)