Primate arrives in theaters on Friday, January 9.

Primate is an inarguably silly movie and yet it leans into that silliness in just the right way. Though it never actually turns into meta commentary or self-parody, you still get the feeling that all involved, starting with director and co-writer Johannes Roberts, knew this should be a goofy good time. And crucially, Roberts also knew it would be best served as a goofy gory good time, delivering a movie far more brutal and graphic than the trailers have indicated, which helps make it an even more satisfyingly over-the-top experience. Seriously, they really should have gone with a redband trailer for this one to more properly sell what it has to offer!

Roberts sets the bar with the film’s in medias res opening, which includes a rather fantastic and attention-getting moment of killer chimp violence that elicited unexpected early applause from the audience I saw it with. I wouldn’t be shocked if the decision to begin with this flash-forward was done in the editing room, because the actual story set-up that follows feels a bit too drawn out for this type of movie. And yet the promise of that opening lingers over everything, as an assurance that we shouldn’t worry; the reason we’re all here is on its way and it’s going to deliver.

The eventual killer in question in the story is Ben, a domesticated chimp living alongside popular author Adam (Troy Kotsur) and his daughters, Lucy (Johnny Sequoyah) and Erin (Gia Hunter), in their beautiful cliffside Hawaiian home. Lucy is just returning home after a long absence in the wake of her mother’s death, with a bit of backstory about her mom being a linguistics expert to explain how Ben came to live with them. If Primate is trying to suggest why you shouldn’t domesticate an animal like Ben, it’s only there as background rather than anything overt or meaningful, but that’s fine for this type of movie. Ben is a loving part of the family until he’s not, and though we get a quick glimpse of the chimp as the sweet-natured guy he always was until now, the movie’s tone ultimately goes to extremes that don’t ask us to cry about the tragedy of what’s happening so much as cheer on the mayhem like we would in a slasher film. If you sometimes end up still feeling Team Ben, well, that makes sense too, because he’s just giving the crowd what they want.

Once we get through the family drama backstory and the unnecessary inclusion of a brewing competition between Lucy and her pseudo-friend Hannah (Jessica Alexander) over the affections of Lucy's longtime crush, Nick (Benjamin Cheng), Primate is commendably lean and mean. The story takes place over one long night as Lucy, her sister, and her friends try to fend off Ben after he snaps and begins brutally killing anyone who crosses his path. At that point, it thankfully concentrates on delivering the goods in terms of tension and exciting kills vs. too many unnecessary elements for a story of this nature. My only big distraction? Trying to figure out why the book signing Adam has traveled to seems to be happening pretty damn late at night for such an event.

This story streamlining (Ernest Riera wrote the script with Roberts) includes skipping past some of the specifics for the how and why of what’s happened to Ben. We know from the start that it’s an oldie but goodie horror set-up – rabies – that will make Ben turn homicidal, as Primate kicks off with a helpful block of text to give us some rabies history. At one point, one character incredulously notes rabies isn’t found in Hawaii, but that line simply serves the purpose of acknowledging this fact rather than leading to a bigger reveal. We never get the expected scenes showing how, say, someone smuggled an animal they shouldn’t into Hawaii that turned out to be carrying rabies…and yet we really don’t need to get that. It’s enough to know that somehow rabies got to Hawaii, a mongoose with rabies bit Ben, and now we’re enjoying the bloody results.

Roberts, whose previous credits include The Strangers: Prey at Night and 47 Meters Down, does a very good job of mixing the straightforward, visceral thrills of his gruesome kill scenes with some genuine moments of tension. He probably has Ben suddenly appear right next to someone a couple times too many, but it works like a charm more often than not. You can also often feel that Roberts is in on the joke, most especially when two horny, drunken douchebag bros (Tienne Simon and Charlie Mann) who are absolutely begging to be massacred by a killer chimp turn up for just that purpose.

The cast, including Sequoyah and Victoria Wyant (as Lucy’s best friend), do solid work in the midst of this innately wacky scenario. Yes, it’s funny to see the charming Kotsur in this type of popcorn movie just a few years after winning an Oscar for CODA, but hey, that’s life in Hollywood. Roberts incorporates the deafness of both Kotsur and his character, Adam, into the story using effective cinematic methods we’ve certainly seen before, including moments of full silence when we cut to Adam’s perspective. Also providing a crucial element is composer Adrian Johnston, who gives the film a 1980s-style synth score that has a cool and creepy vibe.

As for Ben himself, huge kudos to everyone involved in the creation of this character. Rather than using CGI like you might expect these days, Ben was brought to life using an impressively complex animatronic suit created by Millennium FX, with actor and movement specialist Miguel Torres Umba actually wearing the costume and playing Ben. The end result of the partnership between Millenium FX and Umba is that Ben truly looks great; you can easily buy into him as a full-fledged and increasingly angry and deranged character, as he first hunts his prey and then bashes, smashes, and tears them apart in various ways.