First Appearance: Episode 387 (1984)

Last Appearance: Episode 507 (1984)

Known Family: Mother - Heather O'Brien; Father - Mike O'Brien; Sister - Katie O'Brien; Uncle - Jim O'Brien

Key Relationships:
None

Key Storylines:
16-year-old Jeff was only young when his parents decided that the family should move from Melbourne to Perth. He grew up in the Western Australian city and developed an interest in running. In late-1983, Jeff stole a car with a friend, Luke Carlyle, and they went for a joyride. They crashed the car, however, and Jeff's Uncle Jim ended up helping Jeff's mother, Heather, deal with the situation. Luke covered for Jeff to some extent, and so when Jeff appeared before a children's court he was released on a bond but no conviction was recorded against him. Jeff is bitter at his father for getting too involved in his work in Perth, meaning he barely saw him. He is also angry at him for having an affair in Perth with his secretary, Carol, and with his mother for having an affair with Luke's father, Roger. In early-1984, the family moved back to Melbourne.

The O'Briens have only been living in Albert Park for a few weeks when Jeff receives a letter from Luke, which states that Luke has had a big fight with his father, Roger, and his allowance has been cut off; he therefore needs money from Jeff. Jeff cons his father into giving him some money for new running gear and he also undertakes some babysitting for Jill O'Donnel. He sends the money to Luke as recompense for Luke covering for him over the joyriding incident.

During a meal to celebrate Jeff's 17th birthday, an angry Roger Carlyle turns up at the O'Briens', demanding to know where Luke is. Mike and Heather vouch that they haven't seen him. The next day, Luke turns up at Jeff's school. Although he gives the impression that he's surviving, it isn't long before Jeff discovers that he's living in a squat and is pawning his belongings in order to survive.

Jeff becomes hooked on steroids after a new trainer gives them to him and his running mates before the cross-country championships in Brisbane. When Mike eventually finds the drugs in Jeff's bedroom, a huge row ensues and Jeff runs away - but as he runs out into the street, he doesn't notice a car heading for him. It hits him and sends him flying and he suffers serious injuries to his legs. In hospital, the doctors tell him that he'll never be able to run seriously again.

Jeff turns to alcohol to get over his pain and disappointment, and as his addiction worsens, he resorts to petty crime, shoplifting a bottle of whiskey. He's caught, though, and ends up facing a magistrate. He's let off with a good-behaviour bond. There are still problems at home, though, and Jeff ends up moving into an apartment with Luke O'Brien. Jeff's problems worsen when he has a fight with Luke over a bottle of scotch: Luke tries to wrestle the bottle away from Jeff, but Jeff refuses to let go. He ends up hitting Luke over the head with the bottle - and Luke slumps to the ground, hits his head again and passes into an unconsciousness from which he never wakes up.

An increasingly-nervous Jeff never suffers the consequences for his actions, as he is killed when, while drunk at the O'Brien house, he accidentally sets fire to the kitchen and is killed in a resulting explosion.