He was portrayed by the late Maurice Colbourne.
Lytton was a mercenary hired by the Daleks to lead their human troopers, following their loss in a war with the Movellans. Their key objective was to rescue Davros from a human prison station, since they needed his help to cure the virus the Movellans had infected them with. Lytton also monitored the terminus of the Dalek time corridor in 20th century Earth, posing as a police inspector with two fake policemen and killing a group of escaped prisoners.
After the Daleks' initial attempt to board the space station was beaten back, Lytton arranged for a gas attack that killed most of the defenders. He and his men soon had control of the station but he was left frustrated when, instead of removing Davros as planned, the Daleks agreed to let him work in the station's laboratory. Lytton narrowly prevented some of the surviving crew setting off the self-destruct. He was also aware that the Daleks planned to capture and duplicate the fifth Doctor, supervising his capture.
When Davros conditioned several Daleks to serve him and sent them to Earth, Lytton and his troopers were sent after them, but the loyal Daleks were ordered to exterminate him as well. Lytton tried to shoot the Doctor as he released the virus to wipe out the Daleks. Lytton casually killed his surviving trooper and walked away from the carnage with his two policemen.
Stranded on 20th century Earth, Lytton became the leader of a criminal gang, using stolen electronic components to rig up a communicator. He was contacted by the Cryons of Telos, whose planet was occupied by the Cybermen. Aware that the Cybermen had a base in London's sewers, he convinced his gang they were going to rob a diamond merchant and deliberately arranged for himself and his henchman Griffiths to be captured by the Cybermen.
Lytton encountered the sixth Doctor as the Cybermen hijacked the TARDIS to return to Telos. There, Lytton and Griffiths escaped and it was revealed Lytton had been hired by the Cryons to steal the Cybermen's time vessel. However, he was recaptured and had his hands crushed in order to force him to reveal the plan. He was then sent for conversion to a Cyberman. With the process partly completed, the Doctor tried to rescue him but they were confronted by the Cyber Controller. Lytton stabbed the Controller in the arm, which allowed the Doctor to defeat the Cybermen in a brief gun battle, although not before the Controller had beaten Lytton to death in retaliation.
- Lytton's first name, Gustave, was not used on screen but comes from the novelization of "Attack of the Cybermen".