Doctor Who: EVERY NuWho Villain And Monster Ranked Worst To Best

78. Seb

Appears in: The Caretaker, Dark Water, Death in Heaven.

Seb, played with an unfeeling pomposity to a tee by Chris Addison, was Missy's AI assistant who welcomed the recently deceased to the Nethersphere, a Gallifreyan hard drive resembling a cyberpunk city that contained the minds of the dead.

But working for Missy is an occupational hazard, which Seb discovered when she disintegrated him for getting a wee bit too excited watching the Doctor spectacularly escape a plane crash.