The Mentor (Death to the Doctor!)
The Mentor was a rather pathetic overweight villain similar to the Master, specifically the incarnation most frequently encountered by UNIT, so much so that the Doctor briefly mistook him for the real thing. The Brigadier pulled a gun on him.
- The Mentor's subsequent fate remains unknown.
He escaped to Research Base Truro where he met with several other minor adversaries of the Doctor in his various incarnations, who turned on each other as a result of their mutual suspicion. The Mentor died in a three-way shoot-out with Bolog and Plink, two other of the Doctor's very minor enemies.
As with the others, when the Doctor arrived in Truro in the TARDIS, he did not recognize the body. (DWM: Death to the Doctor!)