Cast: Jennifer Garner, Michael Vartan, Victor Garber, Ron Rifkin, Carl Lumbly, Kevin Weisman, Mia Maestro, Greg Grunberg, Balthazar Getty, Rachel Nichols, Bradley Cooper, Merrin Dungey, David Anders, Terry O'Quinn
- Air Dates: September 2001 - May 2006
Sydney Bristow (Jennifer Garner) has to balance an education with a career in espionage, working for a secret branch of the CIA known as SD-6. Believing she is fighting against America’s enemies, Sydney comes to learn that she is the enemy, carrying out covert missions designed to topple the government rather than save it. In response, Sydney, along with her spy father Jack (Victor Garber), become double agents for the CIA, attempting to dismantle SD-6 without raising the suspicion of its leader, the evil Arvin Sloane (Ron Rifkin).
In between, she must deal with growing feelings for her CIA “handler” Vaughn (Michael Vartan), and the fact that her mother Irina Derevko (Lena Olin), a KGB killer, has come back into her life and Sydney simply doesn’t know whether she can trust her. When SD-6 and the Alliance behind it are taken down however, Sydney's life doesn't become much easier as in her new position at the CIA, she heads the manhunt for Sloane who's intent on assembling an ancient device of unknown power with the help of a few allies, some of which are dangerously close to her.
Then it all changes. Two years of her life goes missing, stolen by a criminal group known as The Covenant who brainwashed her. Back at the CIA she attempts to bring down the organisation whilst dealing with the fact that the man she loved is married to another woman, one whose motives seem to be dubious at best, deadly and treasonous at worst. On top of all that, it appears a young woman that is key to Sloane's plans is none other than her half sister.
Soon after, Sydney goes to work for APO - a covert black ops branch of the CIA that answers only to itself. It's an agency that's also is stocked with all the key people in her life who set out on missions to stop the world's most dangerous crims. They've another agenda though - to keep an eye on Sloane who has seemingly given up his pursuit of Rambaldi and through a deal with the Government become their boss. Sydney must come to terms with the horrific truth about what happened to her mother and Jack's responsibility in it. As time goes on, new agendas form and old enemies return including a man very much like the Sloane of old & the last and most brutal of the Derevko sisters.
Having successfully saved the world again and rekindled her romance with Vaughn, Sydney must come to terms with the shock of his revelation about his identity and his sudden demise. As she struggles to re-center her own personal sense of self, she must deal with training both a young woman going through exactly what she went through years before, a disgruntled new agent with a tendency to act before he thinks, the trials of being a pregnant single mother, and a new conspiracy out to try and control the world and who've secretly enlisted Sloane to help do their bidding. She's lived with secrets all her life, and she's done - by year's end Rambaldi's final work will be revealed, two people very dear to her will make the ultimate sacrifice, and she will face the two greatest demons of her past in a final confrontation.