A native of the planet Zephron, Gan killed a Federation officer who killed his girlfriend. He was declared insane and had an implant placed in his brain that made it impossible for him to kill. He was later sentenced to be exiled to Cygnus Alpha. He participated in Roj Blake's escape attempt but was left behind when Blake escaped on the Liberator. When Blake returned to Cygnus Alpha, Gan and Vila were the only prisoners who both joined him and survived the fight against Vargas.
Courageous and powerfully built, Gan, by his own admission, was not terribly bright. But he was the voice of reason and rustic common sense so he was far from stupid. His manner was direct, honest and straightforward. Unlike the other more cynical members of the crew, he took things at face value and was not always expecting to be betrayed or double-crossed. He was loyal and selfless in his devotion to Blake's cause, and his raw physical strength was a great asset. Although loyal to Blake, Gan was noticeably outspoken against Blake's plans to ally with Terra Nostra, a drug dealing organisation.
His implant proved to be an occasional problem, preventing him from killing those who were a clear menace to the crew's safety ("Time Squad") and once breaking down and making him attack the crew and the Liberator itself ("Breakdown"). However, the respect the crew had for him was demonstrated when they went to immense risk to have his implant repaired rather than simply kill him.
During the unsuccessful attack on Earth Control, Gan was killed by falling debris after Travis threw a strontium grenade at the group. He died holding a closing door open so that the others could escape. His last words were, "I'm not worth dying for!" as Blake came back for him. He was the first member of the crew to die and the crew, especially Blake, were devastated by the loss. Blake came to believe that Gan died because the crew of the Liberator (he himself, particularly) had started to believe their own legend of invulnerability.