Jesse was a mechanic and the brains behind Dominic Toretto's operations and was a notable member of Dom's crew. He suffered from Attention Deficit Disorder (ADD) and often stuttered when he was nervous. He was responsible for creating the designs and helping build, repair and restore vehicles such as Brian O'Connor's Toyota Supra with expert precision.
When Brian came to Jesse with a junked Supra, Dom spent $15,000 (in reality $100,000) for its restoration. Jesse did more than just that. He installed an expensive Bomex Bodykit for Brian's Supra. He also equipped it with a dual Wet-Shot Nitrous, that helped Brian smoke a Ferrari F355 Spyder. When he lost the pink slip to his father's 1995 Volkswagen Jetta in a race against Johnny Tran, he drove off the lot, appearing like he was backing out on his deal with Tran. When Jesse later shows up at Dom's house to apologize, Tran and his cousin Lance drive by on dirt bikes and shoot at the group missing everyone but Jesse, who is killed, which causes the pair to be chased by Brian and Dominic in the Supra and Charger.