Kevin Stoney was the managing director of International Electromatics, the world's leading electronics company.

Vaughn made contact with the Cybermen, formed an alliance with them, and then masterminded an invasion of Earth in return for a share of the power. He would claim the entire invasion was his work and the Cybermen merely providing the muscle for his plan. Vaughn was semi-converted into a Cyberman; all the modifications were physical and his mind remained untouched. He intended to betray the Cybermen once the planet was conquered and was aware he couldn't trust them.