Cyber-Leader (Earthshock)

A Cyber-Leader led the Cybermen's attempted destruction of Earth in 2526 and tried to enlist Marc before being driven mad.

Biography
The individual who became the Cyber-Leader endured a painful conversion when he became a Cyberman, enduring blades and a feeling of burning before what it considered to be death. However, its processing meant that it forgot about its life and conversion. (AUDIO: Conversion)

In 2526, the Cyber-Leader was tasked with destroying Earth with a Cyber-bomb to stop a conference that would result in an unstoppable alliance against the Cybermen. However, the bomb failed and the androids were destroyed, leading it to instead plan to use Captain Briggs freighter. It was unsuccessful and attacked the Fifth Doctor, Tegan Jovanka and Nyssa in the TARDIS, where the Doctor ground Adric's golden badge into its chest unit before shooting it several times. (TV: Earthshock)

Whilst its body was destroyed, the Cyber-Leader's core processing was downloaded to another unit. It attempted to recover a partially-converted Marc for use in espionage but was thwarted once again by the Fifth Doctor, whom it called a hypocrite for resorting to violence. Reprogrammed medical nano-drones invaded the Cyber-Leader's body, breaking down its conditioning and causing it to remember its past life, driving it mad. (AUDIO: Conversion)

Behind the scenes

 * This was the first Cyber-Leader to enter the TARDIS.
 * The Leader appears in NOTVALID: The Real McCoy.