Beyus was the leader of the Lakertyans, and when the Rani landed on Lakertya she took him and his daughter, Sarn, as hostages. Beyus collaborated with the Rani as he believed that when had completed her work she would leave Lakertya, and the Lakertyans, alone. He told the other Lakertyans they should do what the Rani asked,but when the Doctor showed him what would happen the Rani exploded her rocket has planned he sabotaged her plans by placing explosive belts around the brain the Rani was using.
When the Rani exploded the belts, thinking they would kill the Lakertyans, they destroyed the brain and killed Beyus.
- Donald Pickering