Trevor was a man who at one point was targeted by John Kramer, better known as the Jigsaw Killer. Therefore, he was subdued, abducted and taken to an unknown location. While he was unconscious, Dr. Lawrence Gordon, John's doctor and one of his apprentices, sew his eyes shut in order to prepare him for a dangerous game. Afterwards, Trevor was taken to a mausoleum along with another victim, Art Blank. Both of them were shackled by their necks and chained to a winch, which was part of a large metal contraption in the center of the mausoleum. (Saw IV, 3D)
Shortly afterwards, Trevor woke up and was immediately frightened when he realized that his eyes were sewn shut. When he noticed the chain connecten to the shackle around his neck, he carefully pulled on it and thereby awoke Art Blank. Upon hearing noises coming from him, Trevor asked who he was and told him to talk to him. However, Art wasn't able to do so as Dr. Gordon had sewn his mouth shut instead of his eyes. As he didn't answer and only made strange sounds in his attempts to speak, Trevor started to panic. Thereby, he stumbled over a wooden crate filled with metallic tools, such as a hammer and a small axe. Frightened by the situation, he threw the tools in Art's direction yelled at him in fear. While desperately trying to calm him down, Art suddenly noticed a key attached to the back of Trevor's shackle. He tried to find a way to communicate with him, but Trevor suddenly pulled him in his direction with the chain. Thereby, a metal pin was pulled out of the contraption in the middle, finally activating the machine and starting the winch in the process. As the winch began to pull them to the middle, Trevor screamed for help and panicked even further. Eventually, he grabbed a hook and began to swing it around blindly. Art calmly approached him, armed with the axe Trevor had previously thrown in his direction. When he saw the right opportunity, he pulled Trevor back to get the key, but collapsed when Trevor ran the hook in his knee. While Art lay on the ground, writhing in pain, Trevor attempted to crawl away, but moments later, Art pulled out the hook from his leg and ran it in Trevor's shoulder, causing him to scream. Thereby, he was able to obtain the key, but Trevor was able to fight him off with the axe. When Trevor attacked him again, Art kicked him in the face. However, as he was ridden by adrenaline, Trevor quickly braced himself up again. As he tried to kill Art, the latter finally grabbed a hammer and bludgeoned Trevor's skull by smashing it four times, ultimately killing him in the process. (Saw IV)
Not much can be said about Trevor's personality due to his short screen time. However, judging by his behavior in the trap, it can be argued that he might have been a man who tended to act rashly in situations of fear and immense pressure.
Trevor is one of the few victims in the series whose reason for their respective test is unknown. However, as most of the victims in Saw IV were former clients of Art Blank, who worked as a lawyer, it's possible that Trevor was one as well.