In many ways, Catfish functions as a better “Facebook movie” than David Fincher’s The Social Network. Whereas Fincher essentially stuck to picking at the genius behind the social networking colossus, this documentary by filmmakers Henry Joost and Ariel Schulman – guaranteed to be one of the most contentious of the year – gives us a more rounded, insightful look at how it all works. The subtle complexities of the site’s user interface – the construction of profiles, friend requests, photo-tagging, sharing of information – are the key catalysts for the film’s central conceit, which, for optimal viewing experience, I shall not divulge – nor should you read up on. Smartly disguised by an ambiguous title that doesn’t make any sense until late in the picture, Catfish has a deceptively innocuous set-up that swings from heart-humping mystery-thriller to painfully intimate confessional with a gripping unpredictability not even the most skilled of screenwriters could possibly dream up. It’s understandable that with the recent trend of fact/fiction-blurring docos – most notably, Banksy’s Exit Through the Gift Shop or Joaquin Phoenix’s I’m Still Here – punters might have their hoax radars working overtime during this one. But whether you buy what happens, or agree with the filmmakers’ ethically questionable actions, one thing you won’t do is finish this doco with nothing to think about.