Trent was very foul-mouthed and considered the "toughest, baddest" kid in the pre-school class. The boys had wanted to play "Firemen", which involved urinating on a fire to put it out. They asked Trent to burn something for them, which he agreed to, as he burned "a lot of stuff".
When the boys failed to put out the fire, it spread and set their teacher, Ms. Claridge, on fire. The resultant burns were so severe that Ms. Claridge would be confined to a wheelchair and could only communicate by beeping once for "yes" and twice for "no".
Trent tried to tell the police that it was the boys' fault, but the boys and Butters, who didn't want to get grounded for being involved, denied it, causing Trent to be sent to Juvenile Hall for five years. As he was being taken away, he swore revenge.
The day he was released from prison, he went straight after Butters, giving him a wedgie so massive it nearly killed him, two "Indian sunburns", a "charlie horse", a "titty-twister", a "swirly", a "noogie", and a "Polish bike ride", causing Butters to wind up hospitalized.
The boys later enlisted the help of the sixth graders to defend them, but Trent overpowered all of them, even giving one of them a "Texas Chili Bowl", involving Tabasco sauce, a telephone, and the anus.
The boys then tried to get the help of Shelly next, but she forced them to confess what they did before she would protect them, seeing as how bullying Stan was her job. As they were about to admit their involvement to Ms. Claridge, Trent arrived to enact his revenge on them. Cartman grabbed the taser he had swiped from his mom, trying to keep Trent away from them, but he shot and missed Trent, accidentally hitting Ms. Claridge's wheelchair and giving it such an electric charge that it was sent out of control, ultimately causing her to get seriously burned once again.
History repeated itself when Trent once again tried to tell the police of the boys' involvement, only to be carted off to Juvenile Hall for another five years, after a misunderstanding of Ms. Claridge's response: after beeping twice, the police officer misinterpreted it as "Yes, yes".
Trent had short, wild blond hair, and wore a black muscle shirt, a tattered red vest, a gold chain necklace, and black pants. He had a tattoo on each shoulder, the left one a skull with "Never Forget", and the right one across with "Vengeance is Mine, sayeth the lord". He also carried around a switchblade with "Kill all betrayers" scrawled on it. He appears to have a nasty-looking glare when vengeful. He always wears his iconic frown and has a pout. Trent is double-chinned.
As a pre-schooler, he wore a similar outfit but had an aquamarine sweater with a picture of a truck on it underneath the vest.
Even in pre-school, he used extremely foul language and was seen bullying another boy for no known reason. Although Trent always had an abrasive disposition, five years wrongfully spent in prison seems to have hardened him and his resolve.
After his release, he was extremely driven by his hatred of the boys, seeking them out and stopping at nothing for his revenge. Butters' attempts at reasoning with him were futile, as were the boys' pleadings at the end of the episode. He is completely ruthless, exacting punishments of extreme brutality on all of his victims. At one point, the doctor remarks, "I don't know what kind of kid would do this to other people; I only know that I wouldn't ever want to be on that kid's bad side".
- Assault: Boyett beat up Butters and the 6th graders. He gave them massive snuggies, wet willies, Indian sunburns, a Polish Bike Ride, a Texas Chili Bowl, a charlie horse on the thigh, second-degree titty twisters, a colossal swirly, head damage, and a noogie.
- Attempted Assault: Boyett tried to beat up the boys, but failed when Cartman fired a taser gun, but missed and hit Ms. Claridge charging her up and making her chair go out of control on a rampage.
- Implied Sexual Assault: Boyett gave at least one of the 6th graders a Texas Chili Bowl, which a doctor said involved Tabasco sauce, a telephone, and the anus. If Boyett penetrated the 6th grader with a telephone, and/or pour Tabasco sauce down his anus, or penetrate him with the bottle, this would classify as sexual assault and therefore make Boyett a rapist.
- According to the DVD commentaries, although some of young Trent Boyett's dialogue contained explicit language, the child voice actor was not required to actually swear. The script contained euphemisms like "doo-doo-heads", which were later bleeped out to sound as if the explicit language was used.
- Trent Boyett's voice was an impersonation of Robin Gibb from the Bee Gees, done by Trey Parker, and his younger voice was provided by Rochelle Leffler.
- He cameos in "Bass to Mouth" on the Eavesdropper website in one of the smaller stories on the right side. He appeared to be in a courtroom.
- The character's lines "Don't tell me that! I heard about the things you've done! But there were no magical Christmas adventures or talking poo for me! I DIDN'T GET TO FIGHT A HUGE MECHANIC BARBRA STREISAND! NO ACCIDENTAL TRIPS TO AFGANISTAN FOR TRENT BOYETT!" reference the main characters' adventures in previous episodes of the show, portrayed in this episode as happening during the years when Trent Boyett was in juvenile hall.