Sounds like the plot for some high-concept psychological thriller, right? Only the title "The Imposter" can't really be classed as a spoiler due to the fact that this shit ACTUALLY HAPPENED.
This is a documentary made up of interview footage and some dramatisation/re-enactment which works surprisingly well. It ploughs similar ground to "Catfish" in that it becomes a study of intricate deception, trust and its abuse, but doesn't have the douchey, art-student protagonists of the Facebook liar flick.
What it does have is a chilling insight into the mind of a man who wants nothing more than to get away from himself, even if it means stealing someone else's identity and family.
It's difficult to write about this film without saying too much, and if you don't already know the story I recommend you avoid it until after you've seen the film as there are enough twists and shocks in this tale to make Hitchcock prick up his fat, dead ears.
And therein lies the problem. It would be easy to dismiss "The Imposter" as exploitative or over-editorialised as it witholds information until dramatically pertinent, shifts emphasis to create tension, and occasionally stoops towards ghoulish prying into a missing persons case. All these techniques make for a well-crafted, compelling film, but may leave you feeling sullied and unusual once the credits start to roll.