A female creature who travelled with the alien entity Light. Light was cataloguing all known life in the galaxy. When he arrived on a new planet, he would send one of his creatures out to interact with the native species, whilst the other would remain on his ship to act as a control comparison. Light would hibernate until the experiment was completed. In Victorian Perivale, Control found herself imprisoned as her colleague had taken on the role of Josiah Smith, and he intended to evolve into what he saw as the ultimate human being - the head of the British Empire. Control succeeded in escaping, and began evolving herself, turning into a Victorian lady.
She freed Light, so that he could put a stop to Smith's schemes. After the Doctor had defeated Light, and Smith had been locked away, Control elected to travel the universe in Light's ship with the explorer Redvers Fenn-Cooper and the Neanderthal Nimrod.
Played by: Sharon Duce. Appearances: Ghostlight (1989).
- Duce is married to Dominic Guard, who had played Olvir in Terminus in 1983.