In Steven C Miller’s intermittently effective film a supermoon turns those exposed to its light into werewolves – or rather people wearing hairy Halloween masks

Intermittently effective but grindingly repetitive, this lupine-themed horror posits a world where nearly a billion people have died after a supermoon turned anyone exposed to its light into a werewolf. A full year has passed, and in an unnamed city (San Juan, Puerto Rico and Los Angeles, California are listed as the locations used) folks are preparing for yet another supermoon-werewolf apocalypse by securing their homes with booby traps and arming themselves to the teeth.

Sensitive yet studly former soldier turned scientist Wesley (Frank Grillo) takes leave of his widowed sister-in-law Lucy (Ilfenesh Hadera) and her daughter Emma (Kamdynn Gary, a strikingly good child performer) as he heads off to help out in a special experiment. At a facility nearby, a team of boffins have developed a kind of “moonblock” that is designed to stop the reflected rays from Earth’s largest satellite from turning people into snarling, uncontrollable werefolk. The science-y bits are insultingly ill conceived, but that’s not really the point here; it’s all about those moments of transformation, the money shots common to all werewolf films, coups de cinema overseen by make-up and prosthetic designers and various effects (both special and visual) teams. Here the actual transitions are quite nifty, featuring lots of bulging veins and grisly-looking in-between stages as people turn into different kinds of snarling mammalian creatures. However, once they are done transforming, the masks or make-up or whatever the actors are clad in are so ineffectual they end up looking like a bunch of underlit extras in Halloween costumes recreating The Purge while howling.