Pre Karate Kid
Jimmy is the most quiet member (having only a couple of lines in the film) and the only brown belt in Johnny's quintet group. At the All Valley tournament, he is the second Cobra Kai to lose to Daniel LaRusso, losing in the third round. Prior to the start of the semifinals, Jimmy is shocked when the teacher John Kreese to put Daniel out of commission.
Karate Kid 2
He is present when Kreese berates and chokes Johnny following his loss to Daniel in the tournament. While he does not attempt to stop Kreese, he shows disgust at Kreese.
Karate Kid 3
Despite not being seen or mentioned, It is implied that Jimmy, along with the other Cobra Kai students, left the Dojo as a result of Kreese's actions following last years tournament.
It was unknown what career path Jimmy took between the years of 1984 and 2018, but judging by his attire of chinos and a button down shirt it is assumed he holds some type of office job or is self-employed in some professional capacity, such as an accountant. Prior to the events of Cobra Kai he married a woman named Jenny and sired two sons with her.
Jimmy isn't seen or mentioned, but is shown in flashbacks.
An older Jimmy along with Johnny and Bobby meet up with their dying friend and fellow former Cobra Kai student Tommy at the hospital. He presents Tommy with a bouquet of flowers, saying his wife Jennifer bought them. Jimmy voices his concern with the arrangements, and they all decide to spend some time together camping before Tommy's passing. Like Tommy and Bobby, Jimmy is shocked when Johnny says that he not only reopened Cobra Kai but also welcomed Kreese back into his life. When Tommy dies Jimmy is saddened, and possibly even in denial as he along with Bobby tell Tommy to wake up. He is next seen flagging down an ambulance, then standing with Bobby and Johnny in shock as EMTs haul away Tommy's corpse.
Jimmy bullies Daniel along with his gang. He, however, is shocked when Kreese tells Bobby to attack Daniel illegally during the tournament, showing he has a sense of knowing when things are going too far.
Karate Kid 2
He disproves of Kreese's disgusting and harsh treatment towards Johnny following the latter's loss in the tournament.
Cobra Kai Season 2
He is concerned over Tommy's condition. When Johnny reveals he reopened Cobra Kai and Kreese has returned, Jimmy voices his concern. He is saddened by Tommy's eventual death. It also is apparent that he has a stable family with his own wife and sons, in contrast to Johnny's shaky relationship with Shannon Keene and struggles to keep Robby Keene on the straight-and-level.
- Jimmy is the only Cobra Kai whose name is never revealed on camera, but only in the credits.
- Tony O'Dell was best known for the 1980s sitcom Head of the Class, where he played Alan Pinkard. Ironically, when Head of the Class had a karate-themed episode, O'Dell's character showed little understanding of the sport.
- The grown versions of the Cobras seem to mirror their attitudes as teenagers. As Jimmy was the most quiet and least vicious towards Daniel, he appeared to have been the most successful at adjusting to adult life. This was in contrast to the vicious attitude of Dutch, who ended up behind bars, or that of arrogant and rather emotional Johnny, who ended up a divorced alcoholic.
- He was the least focused member of Johnny's gang in the original movie.