Brad Travers was a correctional officer at Alcatraz. The first man he killed was a man named Reinkemeyer, who was a gang member at the prison and was holding Travers' superior, Ned Leech, at knifepoint.
During a prison riot, Travers encountered the Seventh Doctor, posing as a prisoner, and a Threckon that had taken over Leech's body. The three were inside a telekinetic bubble created by the Threckon to protect itself from the poison gas used on the rioting prisoners. Travers watched as the Doctor confronted the Threckon, but when the Threckon tried to kill the Doctor, Travers shoved it out of the bubble, killing it.