T.J. Karsten (Henry Thomas) is the son of Thacher Karsten, and a main character in the ABC drama Betrayal. He is the brother of Elaine McAllister, and the uncle of her two children, Val and Vic. T.J. is facing murder charges and being defended by none other than his brother-in-law, Elaine's husband Jack.
Years ago, T.J. Thatcher was very popular amongst the A-List entertainers and socialite. One day, Jack vents his anger all over his love shack and Sara finds him among the broken objects with his bleeding hand. She gets him to open up on that night. TJ wasn’t driving drunk that night but Jack was. Jack drove T.J's Impala and when they crashed into the lake; he at first left TJ. He went back for him but at that point, TJ had lost too much oxygen to the brain. The brain damage TJ suffers from happened because of Jack.
- Son of: Thacher Karsten
- Brother of: Elaine McAllister
- Brother-in-law of: Jack McAllister
- Uncle of: Valerie McAllister
- Uncle of: Victor McAllister