Sydney's dad, Jack, was a CIA double agent working against SD-6 on this Jennifer Garner show
[DOC] [TLE] Alias - Show News, Reviews, Recaps and Photos - TV.com [PAR] Sydney Bristow was recruited as an undergrad to work for SD-6, which she 
thought was ... Sydney approaches the CIA and becomes a double agent, which 
means that she goes ... Sydney's father, Jack Bristow, is also an double agent.