Kirsty Cotton and her husband, Trevor Gooden, are driving in a car, joking and laughing. Trevor states they are going to work out an issue and she agrees. They kiss, Trevor taking his attention away from the road long enough to nearly hit another car. Instead of a head on collusion, their car crashes over the edge of a bridge into the river. Trevor manages to get his seat-belt off, swimming up for air, and screaming for help. He realizes immediately that Kirsty is not with him. He swims back down to the car to find both the doors shut and Kirsty still stuck in the car, having been unable to release her seat-belt. He is helpless, trying and failing to get her out of the car, leaving him to witness her drowning.Trevor wakes up in the hospital, suffering from headaches and amnesia. Kirsty is said to be missing, and her door in the car was open despite the fact that Trevor claimed it was locked. Trevor has nightmares about a surgeon performing painful surgery on him. He watches a tape and sees that he gave the Lament Configuration to Kirsty as an anniversary present.Trevor is in love with his boss, Gwen. But at one point, he has a nightmare where a camera that is recording the room shows (though this is not happening in the room) two Cenobites killing Gwen. Trevor is also in love with two other women named Tawny and Sage, and he has a nightmare where he finds Tawny lying dead in a chair. Pinhead appears and gives him a note saying "All your problems are solved", and the body is gone when next he enters, before he wakes up. When next he sees Tawny, she doesn't remember being with him at all, and is with another man.Trevor soon realizes that Dr. Allison, whom he is talking to, is really a hallucination, when the janitor doesn't see her.It soon becomes apparent that Trevor was not a good man, and was conspiring with his friend Bret to kill Kirsty for her inheritance of Larry and Frank's money. Gwen is said to be dead, and Trevor is suspected for the murders. Only Detective Lange believes he is innocent. Later, Trevor has a nightmare about Bret getting angry at him because their plan was to kill Kirsty and make it look like a suicide, but instead he drove the car into the river to drown her. Bret shoots himself before Trevor wakes up. Later, he has another nightmare about Sage trying to kill him, and when awake he finds her dead, stabbed in the head.Detective Lange enters the room and tells Trevor that it is not his lucky day, because a body was found in the river and Lange takes him to the morgue to see, in the process revealing that he and Detective Givens are the same person, created by Pinhead. Trevor enters the morgue and sees a dead body with a sheet over it. He is about to remove the sheet when Pinhead traps him with hooked chains and shows what really happened. When Trevor made Kirsty solve the Lament Configuration so Pinhead would kill her, finding Trevor bland compared to one who escaped him before, Kirsty offered him five souls in exchange for her own. She killed Gwen, Tawny, Sage, and Bret all by shooting them in the head, and Pinhead took their souls. Pinhead says that only four would not satisfy the deal, and reveals that in the car Kirsty shot Trevor in the head, which was what caused him to crash, and Kirsty was the one who survived. Trevor removes the sheet and finds his own body lying there, and realizes he was the fifth soul, and was in hell the entire time.Back in the real world, after the car crash, Kirsty says Trevor shot himself, and he is believed to have killed the others when the bullets will be matched to the gun. Everyone from Trevor's hell exists in reality, including Allison and Lange, and the surgeon from his nightmares is really a coroner. While discussing the accident and the murders, supposedly done by Trever, Detective Lange pulls out a baggie stating that they found it in the car. Inside it is the Lament Configuration. Detective Lange asks her what it is and she tells him that is was an anniversary gift from Trevor. He says he was going to put it in evidence, but since it was an important and sentimental gift, he will give it to her instead.Kirsty hesitates to take the Lament Configuration, clearly showing how much she does not want it. When Det. Lange looks at her strangely she realizes that if she doesn't take it, it will look suspicious. In the end, Kirsty turns and walks away from the scene, gripping the Lament Configuration tightly.
Output: Question: what kind of injury did trevor have?, Answer: a head injury