It's hard to believe that Ana Piterbarg's Everybody Has a Plan is a debut feature. Starring an exceptionally talented cast the film is led by none other than Viggo Mortensen, and the overall feel of the piece is as self-assured and well-polished as one would expect from a director with years under their belt.

Taking us on a murky journey through dishonesty, delusion, murder and adultery, Everybody Has a Plan tells the story of a man who trades places with his identical twin in order to escape a life he hadn't wanted; only to find himself landed with more than he'd bargained for.

Mortensen's astonishing versatility is packaged neatly here as he plays both contrasting brothers - Agustín, an up-standing paediatrician and Pedro, a gruff, greasy haired bee-keeper with rather less savoury projects on the side.

Although the polar opposites of each other on paper, it soon becomes apparent that each man is a psychopath in their own way. Piterbarg's ability to display with subtle yet deeply unsettling clarity the complexities of human nature leaves the viewer with a feeling that this is one director worth keeping an eye on.

The key female character in the film - Pedro's 21-year-old apprentice Rosa - is written with a depth and consideration that's refreshing, especially within the thriller genre. She is difficult to understand yet highly believable - first falling for Pedro then, without a word, transferring her affections to Agustín even after realising that he's not the man she thought he was. Is what she's really looking for neither Pedro nor Agustín but simply an abstract figure to feel safe with and be cherished by? Does this make their relationship any less valid, any less real?

The film itself is set within the labyrinthine landscape of Argentina's waterways - a mesh of snaking, reedy riverbanks housing a hard-nosed community of people who don't appear to speak much, but who know exactly what's going on in one another's lives nonetheless. Beautifully atmospheric, this remote, hostile environment offers the perfect backdrop to the shady goings on.

Everybody Has a Plan is a creeping, quietly harrowing insight into the sicknesses hidden within some damaged individuals, and perhaps all of us. For a first time feature this is a startling achievement; we look forward to seeing what Piterbarg brings us next.