Danielle Deadwyler is one of the most captivating screen actors working today. But not even Deadwyler can save the dystopian action-horror film “40 Acres,” despite her Herculean efforts.

The feature directorial debut of music video director R.T. Thorne, “40 Acres” is a tale of apocalyptic struggle steeped in Canadian history. Deadwyler stars as tough-as-nails Hailey Freeman, a military veteran and descendant of American runaway slaves who settled in Canada in the 19th century. After a “fungal pandemic” decimated the animal biosphere, resulting in civil war and famine, Hailey and her blended family have survived living in seclusion thanks to hard work and strict protocols. She and her partner Galen (Michael Greyeyes) live in relative peace with their four children, growing their own food and sniping any interlopers.

Hailey’s methods might keep her family safe, but they also put her at odds with her son Manny (Kataem O’Connor), with whom she has a complex relationship. There is no destabilizing force like teen rebellion, and Manny is bored, restless and interested in possibly meeting some girls (other than his sisters). When he balks at killing a young female intruder, we know that Manny might be a problem when it comes to his family’s security, which grows increasingly tenuous.

Every night, Hailey sits in her fortified basement bunker, checking in with neighbors via shortwave radio, and many have gone silent, with rumors of “flesh eaters” on the hunt. The ultimate crack in the wall that lets the evil into the Freeman farm is a predictable one, against which Manny has no resolve: a pretty girl (Milcania Diaz-Rojas) who turns up at their fence, asking for help.

Coming from music videos, Thorne knows how to maximize aesthetics on a budget, and “40 Acres” is heavily stylized, with a desaturated color palette during daylight and high-contrast lighting in night scenes. Drone shots capture the isolated, rural farm in context, and Manny’s moody roaming in the surrounding forest. There are some beautiful shots, especially at night, but throughout, the color correction is pushed a bit to the extreme.

The script — by Thorne, Glenn Taylor and Lora Campbell — is not particularly deep beyond it’s surface world-building. With a sustained slow-burn suspense, “40 Acres” never manages to break out of its tense dynamic, either. Tightly wound Deadwyler nearly vibrates off the screen as the high-strung and hyper-vigilant Hailey. She is riveting, but alone on an island in the film. O’Connor doesn’t have the chops to hold his own opposite her, and Greyeyes is relegated to a role that serves as a warm, often amusing presence, tonally at odds with Deadwyler’s full-bore performance.

If only the rest of “40 Acres” rose to Deadwyler’s level, it could have been one of the most interesting genre films of the year. Alas, despite it’s intense violence, it ends up feeling more like a made-for-TV thriller of the week.

MPA rating: R (for strong bloody violent content and language)

Running time: 1:53

How to watch: In theaters