Sentreal

Sentreal, from the planet Sentreal, (PROSE: Mission to the Unknown) was a representative of his home galaxy at the first meeting of the Galactic Council. (TV: Mission to the Unknown)

Biography
Like the other representatives of the outer galaxies, Sentreal allied himself with the Daleks in their plan to conquer the Solar System in 4000, (TV: Mission to the Unknown) but he did so by accident, having meant to go to the Intergalactic Conference of Andromeda. (PROSE: Sentreal) He did not appear at the seventh meeting, his place taken by Zephon, Master of the Fifth Galaxy. (TV: The Daleks' Master Plan)

Later in the 41st century, Sentreal became a member of the Syndicate. He attacked Ann Kelso, but she was able to control him with a dream machine, and used him to kill Trantis before ordering Sentreal himself to jump out a window, where he fell to his death. (AUDIO: The Perfect Prisoners)

Appearance
Sentreal was a strange half-animal, half-vegetable being, all black apart from two burning bright eyes in his cylindrical head. He wore a black crown and his body looked as though it consisted of several open cones stacked on top of each other, (TV: Mission to the Unknown) which the Fourth Doctor remarked looked like a Christmas tree. In truth, these cones could spin at violent speeds to kill enemies. (AUDIO: The Perfect Prisoners)

Behind the scenes

 * The actor who played Sentreal did not receive a credit, but Johnny Clayton and Len Russell played "Alien Delegates", while Pat Gorman played a "Planetarian". It remains unclear, to date, which of them played Sentreal. Christopher Naylor voiced the role in the Big Finish audio The Perfect Prisoners.
 * Prior to the recovery of episode two of The Daleks' Master Plan, Sentreal and Beaus were often misidentified with each other, including in the novelisation.