Sydney confronts her mother, who reveals her true motivation. Will struggles to figure out who's behind his set-up.

Sydney begins to question Will's identity when he's arrested for espionage, under suspicion of being a double. Meanwhile Sark and Irina plot to recover the Di Regno heart, and Sloane makes Jack a business proposal.

The Agency acts to stop an apocalyptic event prophesized by Rambaldi. Vaughn questions Dixon's state of mind.

Sydney defies her father in her attempt to rescue a kidnapped scientist, while Sloane, seeking revenge, becomes more dangerous than ever. Meanwhile, Allison manipulates an unsuspecting Will for his agency connections.

Sydney faces off with her mother, while Emily Sloane must decide whether to side with her husband or betray him.

Sydney begins to lose trust in Vaughn when she discovers the he is under investigation by the Agency.

Sloane discovers the powers of a mysterious Rambaldi device. Sydney senses that Francie is keeping secrets.

Sydney thinks about leaving the agency. Sloane kidnaps a scientist to help him piece together the mysterious Rambaldi device.

CIA Agent Lennox's identity is called into question by Sydney, Jack and Vaughn after his deep cover mission is blown.

Sydney and Jack scramble to get information on the new Director of SD-6, who is appointed when Sloane goes missing.

Ariana Kane tracks Sydney in order to catch Jack. Sydney and Vaughns covers may have been compromised after sharing a romantic dinner together in France.

Marshall's life is placed in mortal danger. Ariana Kane has her sights set on Jack as the prime suspect in the disapearence of Sloane's wife.

Alliance counterintelligence head Ariana Kane is investigating the disappearance of Emily Sloane. Marshall is sent on his first mission.

While continuing the first family mission together, Sydney and Jack learn where Irina's loyalties lie.

The Bristow family goes undercover on a deadly mission and Mr Sark joins forces with SD-6.

Sydney must make a deal with her nemesis, Mr Sark, in order to find a cure for an ailing Vaughn.

Jack does what it takes to earn back Sydney's trust, while Sydney and Vaughn may have been exposed to a deadly virus.

Sydney uncovers a chilling secret while on a case. Vaughn suspects Jack of setting up Sydney's mother to take the fall.

Sydney's dealings with her mother lead Jack to take drastic measures to ensure his daughter's safety. Meanwhile Will is confronted by a mysterious woman about resurrecting his story on SD-6.

Sydney must stay one step ahead of Mr Sark in retrieving a crucial piece of intel. Jack must face Sydney's mother while Will meets Vaughn.

Sydney begins to question whether her mother is trying to help her or trying to get her killed.

Sydney finds herself face-to-face with her mother, Irina Derevko.