Plutus

 was a member of the Celestial Intervention Agency who became acting Castellan under President Livia. He plotted with Kalbez to make an alliance between Gallifrey and Phaidon and to start a war against the Monan Host. He accused Leela of causing the explosion in the Monan embassy, which he himself had caused by giving Gaal a pass in Raldeth's name. When confronted by Leela, he tried to frame her for an assassination attempt; Livia found out and tried to have him arrested. Instead, Plutus kidnapped her, knowing that the guards would not risk shooting her, but Leela accurately shot him while only crazing Livia. He tried to escape in a TARDIS, but Livia hacked into its destination coordinates and redirected him to Outpost Delta, where Trave put him under arrest.

In the timeline where Romana II and Leela stopped the Moros from becoming a singularity, Narvin arrested Plutus and Kalbez. (AUDIO: Enemy Lines)