As a CIA operative, Evelyn Salt has sworn an oath to duty, honor, and country. When a defector accuses her of being a Russian spy, Salt goes on the run, using her skills and years of experience as a covert operative to elude capture. As Salt tries to prove her innocence, she manages to only raise further questions about her motives. “Who is Salt?”

Sounds like the next blockbuster spy/action hit to come out of ABC/XYZ major gaming studio, no? Alas, this is just the setup for the new Angelina Jolie film that debuts on July 23rd. And while this certainly isn’t the first Fan Immersion Game (FIG) that we’ve seen hit the streets (Jolie’s second, in fact), it is one of the best-yet-developed games of this genre that I’ve seen yet.

Launched on Tuesday, the nine-week adveture seeks to take future film audiences along for the ride on a series of espionage-themed missions that tie into the film’s narrative. The mission of the game (should you choose to accept it) is to ultimately determine, “Who is Salt?” Players will be about to bug suspects, track enemy operatives, and decrypt secret messages.

Dwight Caines, President of Worldwide Digital Marketing for Sony Pictures comments, “This game is built on a series of cliffhanger moments that enhance the moviegoing experience by allowing audiences a unique and truly fun glimpse into the movie. While the missions are serialized, it was also important to create an environment that allows players to join midstream or follow at their convenience. We believe the mystery and action that surrounds the Day X plot, which is central to the film, will keep web fans coming back to the central question – Who is Salt?”

The game is produced by Hoodlum, the same folks that took on the epic project of making alternate reality games based on the hit TV show Lost. “Hoodlum is one of the companies that has set the bar for what an immersive game can be,” said Caines. “They brought high production value to the videos and a creative genius to the missions that will keep this nine-week adventure fresh and fun.”

And if pushing the film wasn’t enough, Sony has even made a clever tie-in to a number of their current electronic gadgets out on the street. The game features a number of Sony products that would certainly find a spot in today’s spy’s toolkit including the Sony Dash personal internet viewer, the Sony Reader touch edition, and the Sony (alpha) DSLR-A850.

Again, this isn’t the first FIG we’ve seen tied to a major studio that is aimed at pumping up interest in an upcoming title, but it is the first that I’ve seen that takes advantage of Facebook, as “Who is Salt?” also features a Facebook Connect feature that not only shares your progress with your friends, but obviously, uses the virality of Facebook to encourage others to join in your missions.

If a little Angelina Jolie clad in tight spywear makes your day go buy a bit faster (and let’s be honest…there are worse things to be looking at all day) head on over to www.dayxexsists.com, where new missions are released every Tuesday until July 13th, 10 days prior to the box office release.