Half-eaten take-aways, dirty vegetables, mouldy cakes, rotting meat – just keep it coming, rats absolutely love them. These fascinating rodents are everywhere, and they will devour virtually anything we throw away. They thrive on our left-overs and excesses and, unlike us, they are not very fussy. They like it very dirty. This movie is based on the eponymous book by Robert Sullivan.

Rats explores the lives of the animals in various parts of the world, uncluding the US, the UK, India and Cambodia. You will see close-ups of the animal, their litter and their extended family in very peculiar places. Just do not expect a David Attenborough-style nature documentary, for you to wow and marvel. These creatures are threatening and disgusting, and the film is instead marketed as a “horror documentary”. We are hardwired to find them repulsive, and that this is for our own security.

“Horror films are much more about what you don’t see,” he explained in an interview with No Film School. “They’re infinitely more about the tension and the drama. What you can build up, making you scared of what might happen versus what’s actually going to happen. I think there’s a lot of moments in the movie where there is nothing happening but there is real tension because you’re just waiting, whether it be for a rat to jump out or the night rat killers to find their prey. It’s great.”

Ed Sheeran has been a rat exterminator for nearly five decades in New York, and he narrates a big chunk of the movie. He justifies his work choice: “Nobody wants to do it, so I’ll do it. I get good money”. He also explains that his relationship to the tiny and yet very intelligent mammals is seemingly based on some sort of negotiation: “I Respect them. If they jump out, I jump back”.

Don’t watch this film if you are queasy, or if you are thinking of eating… ever again. You will see rats in sewers, in ventilation systems, rats being skinned, dissected, and even parasites of all sorts (flatworms, tenias and very strange and large bugs lodged under their skin) being removed from their dead bodies. There are also plenty of images of disease developed in humans bitten by rats, or leptospirosis (transmitted through rat urine, which is pretty much, well… everywhere!).

Rats are in hospitals, nursery homes, expensive restaurants and graveyards. They are in your garbage, in your shoes and inside your cupboards, on your plates and tupperware. They are indeed everywhere. These menacing creatures can kill, and they don’t discriminate. They will come for you whether you are rich, poor, young, old, Black, white, Jew, Arab gay, straight, royal or pleb.

But there’s another side to these vile creatures. They can also be our prey, and end up on our plate, spiced with lemongrass and chilli, and served with onion and lettuce. There are many ways to prepare rat, and they taste “a little like chicken, just a little sweeter”, explains a chef in Cambodia. You might even feel some empathy for the rodents as they squeak in desperation running away from a pack of angry terriers (specialist rat hunters, we are told).

The most touching and unexpected moment comes at the end of the movie, when the director Morgan Spurlock takes us to the Karni Mata Temple in Rajasthan, India. More than 35,000 rats live there in peace with the locals, who perceive them as the reincarnation of their family, and therefore their relatives by extension. The people feed and share time with the affectionate animals. They even share a bowl of milk. It seems like we are not hardwired to find these surprising creatures disgusting after all. Repulsion is also a learnt reaction and behaviour.

Rats relies on effective imagery and interesting anecdotes about these animals, but it lacks some facts and figures. We are told that the animals originated in Mongolia, but we don’t learn much about their numbers worldwide, about their life cycle (how long does a rat live), how large their communities are and so on. Plus the constantly thumping thriller music can be a little irritating. Still this is a very insightful and unusual documentary about an animal that’s probably no more than a few metres away from you right now. It’s time to learn more about close furry friends!

The “horror documentary” Rats is out in cinemas this week at Picturehouse cinemas – just clirck here for the listings.

Watch the nail-chewing film trailer below: