When the mission to kill Vaughn's wife ends up putting Vaughn in the hospital, Sydney decides it's time to kill Lauren. Nadia is forced to decide whether she can trust her father.

Sloane takes the notes that an entranced Nadia has written and pins them to a board, where they form some kind of diagram.

Sloane reveals that he found a Rambaldi text that contained a formula for an elixir that would allow The Passenger to channel a message from Rambaldi.

Sark takes a manuscript regarding The Passenger, called The Restoration.

Dixon explains to the team that a computer worm, originating in Berlin, has targeted hospitals, laboratories and universities. They believe it's a Covenant attack.

Vaughn and Sydney travel to mexico city searching for the key to open the Rambaldi box.

Senator Reed, Lauren's father, arrives to oversee Sark's interrogation. He tells Jack that they must learn the identity of Sark's partner in The Covenant.

Daniel Ryan, a freelance bomb maker whose bombs are impossible to diffuse, destroys a bank in Belfast as a calling card to The Covenant.

Dixon presents the team with a new mission: The Shining Sword, a Filipino terrorist organization, has acquired a next-generation bomb called a plasma charge, which they're shipping to Europe.

At the CIA, the team discusses info gleaned from Lisenker, a Covenant defector.

In a North Korean jail, Sydney passionately kisses Vaughn before they are led, in chains, to a firing line.

Kendall tells Sydney the truth about her two missing years.

Sydney tells Jack about a dream involving Will. Jack advises her to contact Will, who is in the witness protection program.

Hiding out in a warehouse, the team devises a plan to frame The Covenant for Sydney's extraction.

Now in Lindsey's custody, Sydney is imprisoned and tortured at Camp Williams, a secret NSC detention facility.

Sydney wakes from a nightmare in which she sees an angel-like figure, then pulls tubes from her mysterious scar. Shaken, she asks a CIA psychiatrist about the memory-retrieval process.

Sloane tells Sydney that intel about the Covenant's next move is encoded in an image of the Vatican on a website.

Sydney tells Jack to activate the transmitter that she put on Vaughn. Sydney breaks into Simon Walker's room only to find bio-weapon gone and sold to Sark.

A team steals four vials of Ebola from a French epidemiology lab. Lauren and Sydney question Laszlo Bogdan, a team member who was infected and captured.

A fireball drops from the sky, devastating Moscow's Gorky Park.

Jack confronts Sloane, doubting his redemption and blaming him for Sydney's disappearence.

After waking up in Hong Kong, Sydney tries to remember what has happened in the past two years, and discovers that Vaughn is married.