This review was originally published on January 19, 2013 as part of Film.com's coverage of the 2013 Sundance Film Festival.

Simply put, "Sightseers" is a deliciously inappropriate and hilariously weird comedy. It's merciless and unforgiving at every turn, thoroughly British, creepy and beautiful even in the gloriously demented details. While "Sightseers" may not be for everyone, for the brave and blackhearted, it's a fantastic treat.

Timid dog psychologist Tina's life has been defined by her over-bearing mother and the recent death of their beloved dog. When Tina (Alice Lowe) decides to take a caravan holiday with her new boyfriend Chris (Steve Oram), the pair embark on what is meant to be a sexual odyssey, exploring the museums and towns of Yorkshire, but instead quickly spirals into a brutal killing spree as they wind their way across the idyllic landscape.

"Sightseers" is a dark comedy, and wins laughs easily along the way as the script is a wonderful, strange mixture of sharp humor and bleak horror. While it is obviously meant to be hilarious, there's many moments of pure violent brutality that can be difficult to witness, even in the pursuit of looking for laughs. "Sightseers" does not relegate itself to the realm of pure shock or campiness, though; it quickly presents itself as a film worth considering on many levels.

Dynamic, vibrant colors and stylish camera work dominate the British landscape, bringing us into the minutiae of vacation life, from the trinkets strewn about the caravan camper to the details of the savagery wrought by Tina and Chris. The precision and care displayed in the cinematography is evident in the other visual arenas as well, from the simple but effective costuming and spot-on production design. Music plays an enormous role in the story, elevating various individual scenes into the realm of music video fodder, replete with slow motion reactions, almost surreal color and narrative decisions that somehow manage to escape the ridiculous and land squarely and believably.

Directed by Ben Wheatley ("Kill List"), "Sightseers" was written by stars Alice Lowe and Steve Oram. Their performances are so intricate and well done that it's easy to underestimate them. Lowe as Tina is initially awkward, petulant and petty, begging for attention. Chris is all macho bravado as long as he's the one adored and in charge. When both of them are challenged and their true natures begin to surface, all bets are off.

Though we may have our suspicions as to the intentions of these characters from the outside — Tina wishes to escape her life and Chris wishes to impress Tina and they both wish to have a wonderful holiday — the script is written in such a way as to allow for elegantly shifting allegiances. These shifts in tone and structure keep us on our toes and entirely uncertain of where things are headed next, until we simply give up, sit back and enjoy the spectacle before us.

The ever-changing landscape of emotions and anxiety leads the audience on a journey that is entirely enjoyable, though shocking, and "Sightseers" is certainly one of the most original films I've seen in ages. To say too much would be to ruin a remarkable film which is well worth the time of any fan of stern British humor and casual horror. Though it may sound simple enough, "Sightseers" is inevitably far more than the sum of its parts.

SCORE: 8.5 / 10