Marine biology student Siobhán (Hermione Corfield) joins a trawler crew to conduct research as part of her studies but things soon go awry as she and the crew, marooned at sea, struggle for their lives against a growing parasite in their water supply.

Written and directed by Neasa Hardiman Sea Fever is one of those more subtle, quietly haunting horror films. It has a great script and cast but one thing I think it really has going in its favour is it doesn’t try and overly explain the creature. You just see glimpses and Siobhán has theories based on science but nothing is ever proven. Sometimes with “creature features” having to have answers for everything leads to plot holes and an unsatisfying threat. Sea Fever embraces the mystery and having the creature, the parasites and how it functions being an unknown quantity means that there’s always a danger to every decision the characters make.

Though there’s hints of more of a gruesome outcome for the crew, the third act focuses in on the horrors of panicking people rather than the horrors of some unknown creature. Siobhán is a scientist first and foremost and believes everyone should quarantine and not get ashore as soon as possible for fear of infecting others, while the rest of the crew just want to get home and be safe, even if they don’t know whether or not they’ve already been infected. Personally, I thought that worked really well as sometimes a group of people are their own worst enemy. Seeing how these characters react in close confinement and when and how they turn on each other was riveting.

Sea Fever is super atmospheric little Irish indie film and one that I’m really glad I watched. The sound design is great too as is the score by Christoffer Franzén. It suits the tone of the film perfectly and never oversells a moment. 4/5.