It’s a hoary cliché—”things Man was not meant to know”—but in his debut feature, director Richard Raaphorst jolts it back to appalling life, populating Frankenstein’s Army with creations that elicit naked revulsion, as if we’re witnessing something truly obscene. Much credit for that goes to the atmosphere, as the film is presented as shaky found footage of a Russian army rescue mission—a spliced-together and color-faded patchwork that evokes the un-life that confronts the soldiers. As the squad makes its way deeper into a secret Nazi lab, it encounters creatures far from the traditional conception of Frankenstein monsters—if you’re looking for a campy phalanx of shambling Karloffs in Nazi garb, arms outstretched in sieg-heils, look elsewhere. Instead, these are human-machine grafts, with pincer arms, spiked diving-helmet heads, and drilling mosquito proboscises. Designed by Raaphorst and brought to life by Rogier Samuels’s effects studio, Unreal, the half-glimpsed creatures are magnificent and repellent. The film itself works best once most of the soldiers have been dispatched—too often in the first half, the constant running and discharging of firearms proves too similar to watching a first-person-shooter video game. But when one character is finally left to creep around the lab with the camera, the remainder of film takes shape as a grisly haunted house, and the experiments conducted there will set even strong stomachs churning.