Blumhouse Productions continues to have a remarkable effect on American screen horror, making an ongoing array of well-produced features ranging from the rock-solid to the exceptional. While obviously some films have been better than others, the general quality has been so high as to make it one of the most reliable bets for filmed entertainment in the USA. Sweetheart, directed by J.D. Dillard, is definitely one of the company’s less original works. Nonetheless it still provides an entertaining – albeit somewhat generic – diversion.

In the aftermath of a storm, Jenn (Kiersey Clemons) washes ashore on a small tropical island. After several days of securing food and shelter, Jenn discovers there is a mysterious predator somewhere off the coast – a mysterious creature that emerges from the ocean to find prey before dragging it underwater to feed.

Sweetheart is a sparse, short, and broadly effective monster movie, pitting a resilient protagonist against a range of challenges of both environmental and horrific kinds. It tells a familiar story: a woman trapped in isolation, with little chance of help or rescue, pitted one-on-one against a terrifying creature. Despite its generic nature it succeeds via a number of factors including some excellent photography, a strong performance by Kiersey Clemons, and a tight running time that never gives the film a chance to become boring. It is solid, entertaining pulp, and there is always an appreciative audience for that.

Stefan Duscio’s photography is brilliantly effective, taking advantage of the tropical island setting to emphasise both the scale of isolation as well as the oppressive claustrophobia each time night falls. Several shot compositions stand out in particular, notably one moment involving a flare being fired off at night. It is small touches such as this that lift Sweetheart above the run-of-the-mill nature of its story and make it worth watching. Similarly effective is Charles Scott IV’s eerie synthesised score, which is nicely reminiscent of Carpenter-style 1980s soundtracks.

There is an unexpected plot development at the film’s midpoint that re-energises it for its final 40 minutes. There is also an oddly effective use of backstory, in which events prior to the film’s beginning are referred to and implied, but never fully explored or explained. It gives an uneasy edge to things, and a subtle sense of complication.

The title is genuinely odd: it gets referred to in passing, and in the most superficial way, but does not really feel well-connected to the story. One assumes that either Dillard could not think of one better, or that (I suspect more likely) scenes were cut at the scripting or editing stage.

Sweetheart feels like part of a minor wave of ocean-related horror and thriller films hitting big and small screens over the past 12 months, whether arthouse (The Lighthouse), failed studio project (Underwater), or B-grade (Blood Vessel, Deep Blue Sea 3). Sweetheart plays out enjoyably: it is a film that knows what it is and what it is trying to do, and makes the best of its premise with strong acting, production values, and aesthetic. Its audience know who they are, and I suspect will appreciate it well.