Kavil

 was the Science Minister on Gallifrey. When updating the biodata of the citadel, he noted some irregularities in Romana II and Narvin's DNA. He later then identified where the signal that detonated the bomb that tried to assassinate Leela came from. (AUDIO: Emancipation) His specialisation was Wave Form Decryptology. He had detected a signal coming from the fabric of reality, from the vortex itself. The message said Axis. (AUDIO: Evolution)

He tried to strengthen the signal. He told them that the signal was focusing on the Panopticon. After Lord Zakar was returned to the Capitol, he told Romana, Narvin and Leela that the signal was at full strength. When the portal opened, he was exterminated by the Daleks. (AUDIO: Arbitration)