Kebble was a member of Bragen's rebel group on Vulcan. He was assigned to keep watch over the captured Polly Wright. He doubted Valmar could maintain control over the Daleks. The Second Doctor later ran into Kebble and a patrol of guards. The guards were killed by the Daleks, and the Doctor and Kebble escaped down a corridor.
The Doctor found Polly, Ben Jackson and Quinn in the guest quarters and they escaped through a window. Kebble then entered the guest quarters and tried to climb out the window after them but was exterminated by a Dalek. (TV: The Power of the Daleks)