Ref Mawber was an Imperial Security Bureau agent. Mawber was the head of a network of spies which were working undercover in the different criminal syndicates on the planet Questal. He answered personally to the Moff assigned to Questal, Bandor. Mawber ignored that the Rebel Alliance had its own agent watching Bandor's activities, Lanni Peggann, who was Mawber's equivalent in the other side. It was known that Mawber was friends with another ISB agent, Mar Barezz, and that Mawber assisted him during Barezz's obsessive hunt for Rebel agent Tiree.