Episode 1 - The Enemy Walks In
Sydney faces the crisis of her life as, in short order, she must confront her mother, find out what happened to Vaughn. CIA.
Episode 2 - Trust Me
After turning herself in to the CIA, Irina won't communicate with anyone - except her daughter.
Episode 3 - Cipher
Sydney's former nemesis, Mr. Sark, re-enters the picture, trying to launch a satellite with powerful spying capabilities.
Episode 4 - Dead Drop
Past demons revisit all the characters as Sloane becomes confused and desperate over clues that his wife may not be dead.
Episode 5 - The Indicator
Jack's decision to sabotage Sydney's last mission while pinning it on Irina sends his ex-wife to death row.
Episode 6 - Salvation
Sydney's fury at Jack's present betrayal and past sins leads her father to a desperate act to prove his love for her.
Episode 7 - The Counteragent
As Vaughn's life hangs in the balance, Sydney has no choice but to turn to Sark for help in securing an antidote for the virus.
Episode 8 - Passage, Part I
Sark's alliance with SD-6 suddenly puts Sydney at risk of being exposed as a double agent.
Episode 9 - Passage, Part II
Sydney must play peacekeeper between her bickering parents as they struggle to recover a series of nuclear weapons that have fallen into the wrong hands.
Episode 10 - The Abduction
Backed into a corner, Sark cuts a desperate deal with Sloane, using Sydney to recover a state-of-the-art surveillance system.
Episode 11 - A Higher Echelon
When Sydney learns that Marshall has been kidnapped, she struggles against a heartless Sloane to bring him back.
Episode 12 - The Getaway
Sydney and Vaughn reach a crossroads as they try to turn a professional relationship into a personal one.
Episode 13 - Phase One
The entire world of ALIAS is turned upside down, beginning with the mysterious disappearance of Sloane that brings a new head of SD-6 into Jack and Sydney's life.
Episode 14 - Double Agent
When a young CIA agent dies, suspicion immediately falls on her partner and lover, agent Jim Lennox.
Episode 15 - A Free Agent
Sydney finally has the opportunity to leave the CIA for good, but a startling phone call from Sloane brings her back into the fray.
Episode 16 - Firebomb
When Sloane gets his hands on a terrifying weapon, Sydney must turn to a betrayed and hurt Dixon for help.
Episode 17 - A Dark Turn
Jack and Irina forge an unlikely partnership in their attempt to get their daughter out of the CIA for good.
Episode 18 - Truth Takes Time
Dealing with the fallout of her mother's betrayal, Sydney promises that if she gets another shot at Irina ... she won't hesitate.
Episode 19 - Endgame
When the CIA intercepts a secret message, Sydney discovers that the life of Neil Caplan may be in danger from the most unlikely source.
Episode 20 - Countdown
As Dixon struggles with the death of his wife, he refuses to take time off form work until Sloane is brought to justice.
Episode 21 - Second Double
Sydney finds herself racing to clear Will's name when Francis frames him for the CIA intelligence leak.
Episode 22 - The Telling
In this stunning season finale, Sydney Bristow gets one last chance to bring Arvin Sloane to justice... courtesy of her mother, ending with a jaw-dropping cliffhanger.