As seen in the trailers, Ms. Jolie plays Evelyn Salt, a happily married CIA operative who is well-respected for being good at her job (though sporting a very unconvincing blond dye job/wig). Someone needs to tell her that blond does not go well with her complexion. Anyway, that's neither here nor there. On the eve of her wedding anniversary, she finds herself staying at work later than desired to interrogate a freshly defecting Russian agent who then lets it slip that there will be an attempt on the life of the Russian President by a deeply embedded Russian sleeper agent named--drum roll please--Evelyn Salt. But SHE is Evelyn Salt (Dun-dun-dun!!!). As expected, this causes a swirl of chaos within her agency as well as within herself. Her superiors want her to stay put for debriefing but, in her overwhelming panic that her husband might be in danger (as she cannot reach him on his cell), she goes AWOL to check on him. Of course, this sends all sorts of wrong vibes to her superiors and the chase (and distrust) ensues.
With that as a set up, the film tries its absolute hardest to be a twisty-turny-keep-you-guessing-espionage flick. Is she really a sleeper agent? Is it all a terrible misunderstanding? Or is it an elaborate frame up? And to what end? Unfortunately, it's all very predictable. About halfway through the film, the viewer has figured out all the players and their roles so when the final confrontation/revelation takes place, you've already expected it with an audible *groan*. One of the defining factors in terms of the supposed layers of Evelyn Salt is her wonderful marriage to Mike Krause, professional bug enthusiast (yes, really). Thing is, we never get the chemistry between them or why they fell in love with each other. We are just told to accept it in flashbacks and such. So the emotional impact it's supposed to have on Salt is sorta lost on us. If you insisted how concerned you were about your beloved pet fish who all of a sudden stopped eating its favorite food, I'd say, "bummer, dude" and reach for a Snicker's bar. That's about the same level of investment I had with her marriage (not for lack of trying -- I wanted to care, really).
At best, if you want to see Angelina Jolie run around a lot (and I mean A LOT! Way too much time spent on chases) and change her hair color and shoot guns, then just rent this movie or Netflix it. Otherwise, just skip it. Predictable plot points and horrible writing (the dialogue sometimes came down to "Why?" "Because" exchanges) do not deserve your hard-earned $10-12.