Jonathan "Jack" Donahue Bristow was the father of Sydney Bristow and a fellow double agent for the CIA at SD-6. He assisted his daughter in bringing down the criminal organization and assisted the CIA at their base of operations in Los Angeles thereafter. He was recruited to APO, a black ops division of the CIA, by former superior at SD-6 Arvin Sloane, who ultimately betrayed the U.S. government in pursuit of the findings of Milo Rambaldi. Jack was left in charge of APO after this.
In a final effort to stop Sloane, Jack sacrificed his own life to trap an immortalized Sloane in a cave for the rest of eternity.
- ID-CLASS: USS-CI-2300682
- Present Location: Los Angeles
- Place Of Birth: London, Ontario, Canada
- Height: 6'2"
- Weight: 195
- Characteristics: Left-handed
- Training/Special Skills: Physics, Aeronautics, Engineering, Game Theory, Cryptology, Linguistics.
- Languages: English, Chinese, Arabic, Russian, Spanish, Czech
- Education: Doctorate, LAS.