Beyus was the leader of the Lakertyan race, the husband of Faroon and the father of Sarn.
Beyus was forced to serve the Rani alongside his daughter. At first, he refused to rebel against the Rani because of the real threats levelled against his people if he refused to obey her, but was eventually convinced to do so by the Seventh Doctor. He sacrificed himself to destroy the Rani's time brain. (TV: Time and the Rani)