Jayne Kadett

Jayne Kadett was a human undercover investigator in the 41st century, and a companion of the Tenth Doctor.

After a thief stole Cyberman blueprints from the Torchwood Archive and resurrected the army to sell as private soldiers Jayne tracked him to Centuria, where she found he had been converted into a cyberslave. Jayne was then kidnapped by the Cybermen, along with the Doctor, and the pair were taken to Factory Zero-One for cyber-conversion. After they escaped, the Doctor realised the whole planet was likely infested with Cybermen and thousands of lives were at risk. Jayne then joined him to help track them all down. (COMIC: The Power of the Cybermen)

Jayne and the Doctor then detected a hypnotic signal coming from an airship terminal on the continent of Azlon, and upon arrival discovered that the terminal was being used as a cyber-conversion factory, and that a hypnotic beam was being used to subjugate humans and newly-converted cyber-drones. Jayne and the Doctor pretended to be hypnotised in order to enter the facility, and when the Doctor shut down the signal the cyber-drones regained their humanity. Chaos broke out, and Jayne and the Doctor managed to escape before the cyber-factory was destroyed. (COMIC: Drones of Doom)

The Doctor and Jayne then visited Centuria's arctic in search of the Cybermen's base. In the frozen wastes they encountered Homaj, a semi-converted cyber-drone who had retained his humanity, who had escaped from a hargstone mine which was being run by the Cybermen. When the trio were attacked by ice snakes, who were then killed by Cybermen and their cyber-converted dogs, Homaj fled. Jayne and the Doctor were captured and taken to the mine. Once inside, the Doctor created a distraction while Jayne stole some explosives. The pair escaped and found Homaj waiting for them outside. He took the explosives from Jayne and sacrificed himself to seal the mine. Jayne and the Doctor then left in pursuit of a recently-departed Cyber-ship, which was headed towards Centuria Central. (COMIC: Enemy Mine)

The TARDIS then arrived in Centuria Central, which had been frozen by a temporal stasis field. Jayne was caught in a time-trance, unable to move, but the Doctor could resist the field because he was a Time Lord. The Doctor worked out that the Cybermen had been gathering hargstone to maintain a temporal stasis machine. This machine was telepathically linked to each of the planet's Cybermen, allowing them to move freely within the stasis field. When the Doctor destroyed the machine this produced immense temporal feedback which disabled all of Centuria's Cybermen. With the Cyberman threat apparently eliminated, the Doctor and Jayne parted ways. Before he left, the Doctor warned Jayne to her to keep her eyes peeled. (COMIC: Time of the Cybermen)