There's some oddly similar films out at the moment. The A Team and The Expendables are military team movies. Knight and Day and Salt are spy movies. In The A Team, Knight and Day and Salt, the protagonists are on the run for a crime they didn't commit. The A Team and Knight and Day are played for laughs. The only thing you can't see at the moment is a Team Military movie in which the protagonists aren't on the run for a crime they didn't commit, but which is played for laughs.
Anyhoo, Salt is Spy, Serius, Running Away. Evelyn Salt is a CIA officer who is outed as a Soviet Mole, by a defecting Soviet spymaster who claims that there was a programme of training kids from childhood to be moles in the US, which was so extensive that it's not so much a espionage plot as an immigration policy. I mean, sod activating them and having them kill important figures, it sounds like these moles practically run the US. In fact, it looks very much like they could get a Russian picked President into the White House just by voting him in, there's that many of them.
Anyway, Salt protests her innocence, insists that she's off to protect her husband, then essentially goes radio silent. From that point on in the film, she barely speaks at all, and all we, the viewer have got to go on is her actions, which from the outset don't entirely seem to be those of an innocent woman. This leads up to a point about halfway through the movie which is a genuine "Wha...? Bu...? Huh?" moment. From that point on things get a little bit chaotic, as Salt's actions don't entirely seem to satisfy any explanation, until you work out what's really going on. This leads us nicely to the finale, which you should see coming if you're awake, but if you're either not too bright or suffering from a cold (like I am), it might catch you unawares. Cut to the post-finale wrap-up, we set ourselves up for a sequel, job done.
It's a workmanlike bit of plotting, an ambitious storyline, couched in fairly pedestrian dialogue. In terms of how it looks and moves, it's like a Jason Bourne sequel (i.e. not as good as The Bourne Identity, but the same idea). The ethos is "this is the real world, but the fighting and stunts are bordering on superhuman." Salt is very competent, quite ruthless, and her motives aren't entirely easy to guess. As such, it's a clever enough "Hollywood Blockbuster", but it's a four piece jigsaw compared the the Rubik's Cube that is Inception.
* - sadly, not a revisionist Veruca Salt biopic.