Celebrating its 40th anniversary this year, Colin Eggleston’s eco-horror Long Weekend is finally released on Region 2 Blu-ray.

Thanks to Jaws and other animal-attack based movies, this sub-genre was thriving for most of the 70s. Shot in 1977, Long Weekend sat idle on a shelf for almost two years before it saw the inside of a cinema. Thankfully the film did arrive in cinemas in 1979 and has enjoyed a cult following over the years.

For what is essentially a horror film, Eggleston breaks the mould by having almost no dialogue in the first half an hour. Ordinarily, this bold move could prove to be alienating, but we learn so much about couple on the rocks, Peter & Marcia, that excessive dialogue would have been a distraction. They casually discard their litter, flick their cigarette butts, and barely flinch when they merrily run-down wildlife in their gas guzzling car. Basically, they’re the worst.

The couple in question are looking to salvage their crumbling relationship by getting away from it all for a long weekend in the countryside. However, the more their obnoxious attitudes disrespect the environment; the more their relationship deteriorates until nature strikes back. A slow burn first act gives way to surrealism as the film progresses, we’re not talking Lars Vo Trier AntiChrist levels of surrealism, but things get decidedly odd.

While they get first and second billing respectively, stars John Hargreaves and Briony Behets are not the heroes of the film. We’re not meant to be rooting for them to come out of this as better people. There’s not much room in Everett De Roche’s (Patrick) script for subtlety, but this isn’t an exercise in subtlety and the heavy handed approach works wonders. Despite the wealth of hints that nature dolls out to this couple, they simply refuse to mend their ways, and pay the price for it.

Forty years on from release and Long Weekend is still a haunting parable for humanity and its constant mistreatment of the environment. Sadly, it’s a lesson that the planet has yet to learn and Long Weekend still serves as a stark metaphor. Ignore the 2008 remake that starred Jim Caviezel (it currently has a 0% rating on Rotten Tomatoes, so most people did ignore it); Colin Eggleston’s is an underappreciated gem that has something to say that is eerily relevant today.

Long Weekend is out now on Blu-ray courtesy of Second Sight.