As both a movie based on a video game and as a werewolf movie, Werewolves Within is a terrific surprise.

Based on the Ubisoft game about a medieval town beset by a werewolf disguised as a resident, Werewolves Within stars Sam Richardson (Veep) and Milana Vayntrub (This is Us) as the seemingly only sane residents in a modern town full of kooks. The movie from IFC Films was released in select theaters on Friday; it goes to VOD on July 2nd.

Richardson is Finn Wheeler, the new Forest Ranger in the town of Beaverfield in snowy New England, and Vayntrub is Cecily, the town’s mail person, who is also a new resident. The two meet in the large cosy inn, run by Jeanine Sherman (Catherine Curtin).

The town residents (few that there are) have their quirks, to put it mildly. Jeanine the inn-owner is depressed after her husband ran off with another woman. Wayne Duvall (Sam Parker), the gas company rep who is staying at the inn as he tries to sell the town on a gas pipeline that will be built under their community, possibly damaging the area’s ecosystem.

Three quirky couples serve as the rest of the town: rowdy Marcus and raunchy Gwen (George Basil and Sarah Burns) who run the auto show; handsy Pete and high-strung Trisha (Michael Chernus and Michaela Watkins), who run a craft store, and pretentious yoga studio owners (and tech-millionaires) Devon and Joaquim (Cheyenne Jackson and Harvey Guillén).

Dr. Ellis (Rebecca Henderson), an environmentalist who is staying at the inn to convince the townspeople to vote against the gas pipeline, and Emerson Payne (Glenn Fleshler) a dangerous and armed illegal trapper who lives in a cabin on the outskirts of town round out the cast.

Something mysterious attacks the town’s power supply the same night as a blizzard hits; even the generators are disabled. Trisha’s little dog Chachi meets a grisly end, leaving behind some mysterious hairs and a mangled leash. With no power and no way of leaving, everyone (except Flynn) heads to the inn to find out what’s wrong. Things are further complicated when the maimed body of Jeanine’s husband is found under the house. Ranger Wheeler tries to take charge of the hysterical townsfolk as they wait for Dr. Ellis to identify the type of creature that dispatched both Chachi and Dave Sherman.

Of course, once everyone is locked in the inn, another attack occurs and the movie becomes a whodunnit rather than a straight-up horror film as the cast turn on each other – even violently – as they attempt to find the culprit while also proving themselves innocent. Dr. Ellis gets the results of the DNA test: the culprit is a lycanthrope. With the news that the werewolf is calling from inside the house, thus begins a frenzy of mayhem (some of it self-inflicted) and murder pitting Finn and Cecily against all the other townsfolk.

A ‘which one is the werewolf’ whodunnit isn’t new; 1974’s The Beast Must Die did the same thing at an English country mansion. But Werewolves Within adds an enjoyable element of dark comedy to the story. The acting (especially Vayntrub, known mainly for her AT&T commercials, and Henderson) and writing are top notch. Author Mishna Wolff (I’m Down) adapted the screenplay and actor/director Josh Ruben (Scare Me) deftly combine humor and horror to make a movie that isn’t short on either.

While the movie’s concept is taken from a video game, the story feels original and fresh, and the characters (love them or hate them) are fun to watch. Movies based on video games can choose style over substance but Werewolves Within leans into the silliness of the situation with charm and humor, making a movie that is an absolute delight to watch. You may or may not guess who the is the werewolf before the reveal, but either way, you’ll enjoy this movie.