Horror films that try to combine a science-fiction theme with mysticism usually fail but this is one of the better attempts at it that I’ve seen. It’s also the first film we’ve seen that was made during the covid-19 pandemic and is set during the pandemic itself. Apparently director Ben Wheatley had gotten bored while everything was shut down and made this in a mere 15 days. This is still a quick film made on a small budget and a tiny cast and there are limits to how much one can achieve in this way but this truly is a solid horror film.

Even as most people are on lockdown, scientist Martin Lowery goes to somewhere even more remote, in the middle of a forest with restricted access. He is to join a former colleague Olivia Wendle in her project studying mycorrhizal association. A park guide, Alma, takes him on the two-day trek to Olivia’s camp and she tells him that due to the pandemic and her own seclusion, Olivia has not been seen in months. On the way while they camp overnight they are attacked by unknown assailants who steal their gear and shoes. Martin’s foot is badly injured as they continue on barefooted. They encounter Zach, a man who seems to be living in the forest illegally. He offers them shoes at his own camp and also disinfects and stitches Martin’s foot. However this is a ruse as he offers them a drink that sedates them. While they are half-conscious, Zach dresses them in white robes and takes photographs of them in strange, ritualistic poses. He also stitches a strange symbol on Martin’s arm that he claims will make him more visible to the strange entity that controls the woods. Eventually they escape and make it to Olivia’s camp but she too believes in the entity, which she claims is the fungal network centered on a strange standing stone and reaches throughout the entire forest.

This is a simple film and it works mostly because it takes such a matter-of-fact straightforward approach and is so plausibly grounded. The opening scenes of Martin arriving at the government outpost wearing a mask, having to go through decontamination and needing to be quarantined while he gets tested all reinforce the impression that this takes place in the here and now. The film also doesn’t indulge in jump scares or dramatic camera angles seen from outside the perspective of the protagonists. Even the premise of the entity being a fungal network whose tendrils extend across the forest and possibly farther away, and can influence the behavior of the plants it is connected to, is based on relatively new research and so feels current. There are some hints of the supernatural with Olivia pulling out an ancient tome on witchcraft but this too is reinterpreted as ancient peoples encountering the mycorrhizal entity and rationalizing it as being demonic. It’s all put together very well and feels consistent.

One of my favorite things about this film is the characterization of the villain. Having a stranger show up out of nowhere to offer you new shoes just after you’ve lost your own is of course extremely suspicious. Yet Zach seems just cautious of the two as they are of him. Human socialization instincts are so strong that you can see Martin and Alma feeling how impolite it would be to openly wary when he is offering them food and drink. He even gets out a guitar as if to entertain them but of course it’s to make them more relaxed so that the sedative works better. The director also understands that the anticipation of an act is violence is worse than the blow itself. So Zach talking Martin through the process of partially amputating his infected foot is capable of inflicting so vicarious pain on the audience. All these touches add up to making this a very effective horror film.

As I noted there are inherent limits to how far the director can stretch this kind of film. It’s crazy how much equipment Olivia has in her camp for it just being herself and it doesn’t make sense why an alarm wasn’t raised earlier if Zach had multiple previous victims as the film implies. Plus the fungal entity is so inherently alien so we have no idea what it even wants. It’s good then that the director doesn’t try to drag things out too much or overexplain things, allowing the film to naturally end just as it peaks.