Sydney Anne Bristow (played by Jennifer Garner) is a fictional character and the protagonist of the television series Alias.

Sydney is highly skilled in Krav Maga and is a hyper polyglot, speaking English, Russian, German, Greek, Dutch, French, Italian, Spanish, Portuguese, Norwegian, Swedish, Romanian, Hungarian, Hebrew, Uzbek, Arabic, Persian, Urdu, Indonesian, Cantonese, Mandarin, Japanese, Korean, Hindi, Vietnamese, Polish, Serbian, Czech, Ukrainian, and Bulgarian in various episodes.

When Sydney was 19 years old and a freshman in college, a man approached her and told her that he worked with US intelligence and that they wanted to interview her because she fit a profile.

After meeting with an organization she believed was the Central Intelligence Agency, she signed "dozens of non-disclosure agreements" and was offered a job.

They had Sydney take a job as an office assistant on the twentieth floor of Credit Dauphine, a corporate bank in downtown Los Angeles.

Sydney was told that the objective of SD-6 was "the retrieval and study of intelligence, both military and industrial, throughout the world that is critical to the superiority and survival of the United States of America."

Seven years after joining SD-6, Sydney discovered that SD-6 was actually a branch of the Alliance of Twelve, an international organized crime group involved in the trade of intelligence and weapons, and was an enemy of the United States.

During this season, the head of SD-6, Arvin Sloane, was obsessed with Milo Rambaldi, a man from the 15th century who was able to create brilliant devices that were far ahead of their time.

Midway through the season, the CIA finally has enough information to bring down the entire Alliance organization and the assault on SD-6 headquarters, led by Sydney and Vaughn.

During this time, Sydney's friend and roommate Francie has secretly been assassinated and replaced by an agent of Sloane and Sark's, Allison Doren.

Sydney now has to deal with the pain of not knowing what has happened for the previous two years of her life, but also the fact that Vaughn is now married to another woman, National Security Council liaison Lauren Reed.

Eventually, she wiped her own memories to conceal information and perhaps also because of the horrifying realization that the Covenant had extracted her eggs in order to fulfill one of Rambaldi's prophecies.

She was also greatly disturbed that she chose to kill an unarmed man in cold blood rather than risk losing her cover as a brainwashed assassin.

Following a botched mission in Shanghai, she receives a dressing down at a performance review, is demoted, and is subsequently dismissed from the CIA.

Much to her dismay, this new agency is headed by Sloane, who oversees a handpicked team which includes Sydney, Jack Bristow, Vaughn, and Dixon.

During the course of APO's first mission, to bring down a terrorist and assassin-for-hire, she learns the man was actually hired to kill her - by Irina.

Around this time, after some twists and turns and ups and downs in their relationship, Vaughn finally proposes marriage prior to the mission to go after Elena.

Shortly thereafter, Sydney learns she is pregnant and Vaughn is shot and apparently killed by a rogue agent posing as a CIA officer.

Sydney finds a kindred spirit in Rachel Gibson, a young, wide-eyed, inexperienced agent rescued from "The Shed", a covert criminal organization that, much like SD-6, operates under the alias of a CIA black-ops division.

Now a member of APO, Gibson is learning the ways of being a field agent, with Sydney her designated handler, just as Michael had worked with her.

However, in the episode "Solo", she came to realize that these days might be fast coming to a (temporary) end when she is not allowed to go on a mission due to her condition.

Three weeks before her due date, Sydney is captured by Prophet Five in order to force her (via a form of drug-induced hypnosis) to remember details of a giant SD-6 flowchart that she had been shown by Michael Vaughn during one of their first meetings.

Encouraged by her mental recreation of Michael Vaughn, she is able to resist the hypnosis and provide false information to her kidnappers (who, unbeknownst to Sydney, include Irina).

Sydney discovers that she has been stranded aboard a freighter at sea where she attempts to elude Prophet Five and one of their associates, Kelly Peyton.

About a month after giving birth, Sydney returns to duty when Anna Espinosa is recruited by Peyton to kidnap Will Tippin.

Espinosa implants an explosive in Tippin's head and demands that page 47 of Rambaldi's manuscript be turned over to her in return for the disarming code.

After Anna kills Renée Rienne while she is on a mission with APO, a chip bearing Michael Vaughn's real name (André Michaux) is discovered implanted in her body.

Sydney disrupts Sloane's plans by grabbing the Horizon from the altar, causing the ball to collapse in a torrent of red liquid.

Isabelle has found the blocks for Project Christmas and assembles them in no time, but dismantles it after Sydney calls for her and she joins her family outside.

In August 2003, the actual CIA enlisted Jennifer Garner to appear in a recruitment video, which would be shown at fairs and college campuses.