Charles Gunn, or simply Gunn to all his friends, is a young man whose strength has been greatly improved by his harsh childhood. Having to deal with death from an early age, and having little or no support, Gunn soon knew exactly what he had to do to take care of himself. Seven years before meeting Angel, he had no aims or hopes for the future, and so traded his soul at a casino in order to get the truck he now treasures. When he later falls in love with Fred, he ends up needing Angel's help in order to help save his soul.

During his early years in Los Angeles, Gunn became the leader of a gang of young people going after vampires, and protecting the innocent people who walked the streets at night. This worked well for many years, with Gunn's gang tactics saving many lives. However, when he first meets Angel, things get turned upside down. First of all, a vampire with a soul, one who cares for people, and tries to help them, then worst of all, his sister is turned by a vampire, and Gunn is forced to kill her. He has grown up the hard way yet again,

Though at first Gunn only does favours for Angel, he soon becomes a regular member of Angel Investigations, and soon has regular pay from Angel. Though he, along with Cordelia and Wesley are fired during season 2, he is now back with Angel, and remains extremely loyal.