Like the others, Sentreal allied himself with the Daleks in their plan to conquer the Solar System. (TV: Mission to the Unknown) He did not appear at the seventh meeting, his place taken by Zephon. He seems to have returned by the time of the final meeting, however, perhaps because Zephon had been exterminated. After he was betrayed by the Daleks, he was convinced by the First Doctor to go back to his own people and warn them about the Daleks' invasion plans.