Alias

Sydney, Vaughn, Jack and Dixon get a new boss, Sydney and Vaughn question whether they'll ever be able to reconcile their relationship, Sydney learns a terrible secret about her father, and Nadia is reluctant to return to the spy world since learning the truth about her father, Sloane.

Sydney, Vaughn, Jack and Dixon get a new boss, Sydney and Vaughn question whether they'll ever be able to reconcile their relationship, Sydney learns a terrible secret about her father, and Nadia is reluctant to return to the spy world since learning the truth about her father, Sloane.

To learn the location of a stolen NSA code-breaker, an undercover Sydney must convince a murderous arms dealer to fall in love with her. Meanwhile, Vaughn fears that Weiss might have been killed on a mission, and Sydney and Jack argue about telling Nadia the horrible truth about her mother.

Sydney tries to buy a bio-weapon called Ice 5 from an American at a foreign bazaar.

Sydney and Vaughn pose as Chechen spies, living in a bizarre fake American suburban town in Russia.

Sydney starts to lose touch of the world when she gets altered by hallucinogen, and Jack and Vaughn look for a cure.

Sydney and Nadia argue over Sloane's new behavior, fatherly behaviour.

Sydney is assigned to stop her old nemesis Anna Espinosa. Vaughn visits Sark in the federal pen.

Sark agrees to help Sydney and Vaughn track down Anna Espinosa, but only after Vaughn agrees to a despicable request from Sark related to Lauren's buried corpse. Meanwhile, Jack ponders risking Nadia's life by prematurely reviving her from an induced coma to extract vital information about Anna's whereabouts.

Sydney's theory that Sloane is trying to re-form the Alliance threatens her relationship with Nadia, who refuses to believe her father is double-crossing the CIA. Meanwhile, Vaughn learns the first of possibly many startling secrets about his father.

While on a mission in Germany, Sydney inadvertently places the life of an American civilian in jeopardy and must do all she can to get him out of harm's way. Meanwhile, Jack plans a deadly visit with an old friend, and Vaughn uncovers even more unsettling secrets about his father.

After failing to disclose her tainted past with a man who is now the focal point of the agency's mission, Nadia places her life as well as the lives of Sydney and Weiss in grave danger. Meanwhile, Vaughn discovers someone with ties to both his father and Nadia.

When a mission does not go well, Sydney is attacked and her life is placed in danger. The only one who can save Sydney is Marshall.

Jack agrees to Sydney's request for clearance on files relating to Vaughn's father.

Dixon is shot by a masked gunman. The shooter approaches and takes off his mask, revealing Vaughn.

In Poland, men posing as airport guards abduct Professor Sinclair, a nuclear physicist. She wakes up bound in a dark room and is greeted by a man impersonating Arvin Sloane.

Sydney and Nadia are shocked to discover that Sophia -- the head of the orphanage that cared for Nadia as a child -- has been severely beaten. But Sloane fears for Nadia's life when he learns the reason for the beating. Meanwhile, Dixon is faced with a life-altering moral dilemma while on a mission with Vaughn. Jack's doctor offers some advice to his ailing patient.

Sydney tells Vaughn that she hasn't seen her father in two days. They go to his apartment and find a notebook with recent records of Jack's vitals.

The mysterious man, who has been impersonating Sloane resurfaces, and this time he's hot on the trail of Rambaldi. Meanwhile, shocking revelations about the real Sloane are brought to light, causing everyone to further question his true intentions.

After learning the awful truth about Nadia's childhood caregiver, Sophia, APO races to track her down while an agent's life hangs in the balance. Meanwhile Sydney and Nadia question Sloane's trustworthiness now that his obsession with Rambaldi may have been renewed, Jack has an unsettling meeting with Katya Derevko (Isabella Rossellini), and Vaughn asks Jack a surprising and momentous question.

Upon discovering that Irina Derevko is alive, Sydney, Jack and Nadia set out to find her in order to thwart Elena Derevko's deadly Rambaldi endgame. Meanwhile, Dixon's condition takes a turn for the worse.

Sydney, Jack, Irina, Vaughn and Nadia are the last hope to save the world from the catastrophic effects of the Rambaldi end game, put into action by Elena Derevko. Meanwhile, the Rambaldi prophecy surrounding Sydney and Nadia comes one step closer to becoming reality, Sloane's true allegiances are realized, and Vaughn asks Sydney a momentous question, on the season finale of Alias