Director/documentarian Bart Layton cut his teeth most notably as the creator and executive producer on National Geographic Channel's Locked Up Abroad. The Imposter feels very much like that style of show. That statement isn't meant to marginalize the film at all; but it was co-produced by A&E IndieFilms, and oen should prepare oneself for an according aesthetic.
Having put that preface out there, The Imposter is one crazy story. There are so many twists and turns--and really, so much of the enjoyment of the film relies on them--that getting into the plot is likely doing a disservice. The titular imposter is exactly that, but the story goes much further than that of a young Frenchman taking the place of a missing San Antonio boy. It's bizarre, upsetting, amusing, puzzling, and surprising. Most importantly, The Imposter is pretty goddamned entertaining. As it is a documentary, it will surely be on Netflix Instant soon. Go get some.