G is for... Gunslinger

In order to end a long and bloody war, a scientist named Kahler-Jex experimented on a group of volunteers to create a cyborg weapon. Many died in the process. The creatures proved a great success as the war was brought to a speedy conclusion. All of the cyborgs were then terminated, but one managed to escape. This was a man who had once been Kahler-Tek. He decided to eliminate everyone who had worked on the cyborg programme and pursued the last of the scientists to Earth, arriving in the small town of Mercy, Nevada in 1870. Here Khaler-Jex had ingratiated himself with the townsfolk, giving them medicines and electrical power. Tek, meanwhile, waited outside of Mercy, as he was programmed not to hurt any innocent bystanders. He became known to the locals simply as the Gunslinger. He laid siege to the town. When the Doctor, Amy and Rory arrived in Mercy, the former identified himself as an alien doctor - which is what the Gunslinger was demanding. The townsfolk tried to give the Doctor to Tek, but the Gunslinger knew he was not the one he wanted. The Doctor discovered Jex's spaceship and accessed records of the experiments, which showed that he was a war criminal. He returned to the town and was prepared to hand Jex over to Tek. The town sheriff was accidentally killed by the Gunslinger, and it issued an ultimatum to the town to hand Jex over by noon the following day. The Doctor, meanwhile, found himself taking over as sheriff of Mercy. Although he despised Jex, the Doctor devised a plan to help him escape from the town when the Gunslinger arrived. However, Jex had come to see the error of his ways and, knowing that the cyborg would never rest in hunting him down, he decided to kill himself by self-destructing his spaceship. Kahler-Tek was prepared to kill himself now that he no longer had any purpose - but the Doctor convinced him to stay on and act as law-keeper for the town.

Played by: Andrew Brooke. Appearances: A Town Called Mercy (2012).