Shane Carruth follows up his impressive, confounding 2004 time-travel mindbender, Primer, with this equally ambitious science fiction thriller. Less easy to pigeonhole, Upstream Color is the story of a young woman, Kris (Amy Seimetz), who is drugged, abducted and hypnotised by a mysterious man, referred to only as The Thief, who then cons her into emptying her bank accounts before abandoning her.

As Kris struggles to put her life back together, she meets Jeff (Carruth), another shifty stranger with whom she seems to have nothing in common, but may in fact have suffered a similar ordeal. Add into this bizarre, at times disorienting soup of visual and aural stimuli another enigmatic character – The Sampler – who wanders the countryside, recording snippets of sound in order to make ambient music, and you begin to have an idea of what Upstream Color has in store.

The less known about the film the better, for the very reason that attempting to piece together the various, perhaps unrelated fragments is half the fun of watching it. The film is a puzzle that will keep you occupied for hours, if not days after the credits roll, and which begs an almost immediate re-watch.

Carruth serves as writer, editor, director, star, composer – among other roles – and it soon becomes obvious that Upstream Color simply wouldn’t have been possible as a more collaborative effort. It is such a unique concept and vision, executed so meticulously that it can only have come from a single warped mind. That said, it is Seimetz’s central performance that pulls all these dispirate threads together into something resembling a coherent whole. The film charts her journey, first one of rediscovery, as she attempts to retrieve her memory, but later one of exploration as she begins to comprehend how she has now changed.

From this vague, perhaps even incoherent description, Upstream Color might sound somewhat impenetrable and pretentious. Perhaps it is the latter, but events are laid before the audience clearly enough, and the film is never a chore to watch. It certainly demands your full attention, and is unforgiving of those not committed to keeping up, but dedicated audiences should find their efforts rewarded many times over.

Without even touching on crucial plot details, like the maggots, pigs, orchids and the “blue”, there is enough in the performances, photography and incredible sound design to warrant a wholehearted recommendation. What the film is actually about, what it is hoping to achieve or actually say is an impossible conversation if you haven’t seen the film for yourself, suffice to say that it touches on memory, identity, trust, and the interconnectedness of all living things, in profoundly unique and engaging ways.

Upstream Color is likely to confound and haunt viewers and represents the kind of cinematic experience that is all too rare in this day and age. Carruth challenges how we engage with his film, and that is something that should most definitely be encouraged.