Two hot chicks show up at your door, soaking wet and flirtatious as hell. What would you do? If you were Keanu Reeves, you’d let them in and then be coerced into having a threesome—a lethal mistake considering that the two young ladies are psychotic and will take you hostage, torture you and potentially kill you for being a sleazy bastard.

Such is the premise of Knock Knock, a thriller from director Eli Roth. Though self-declaring himself a “horror master,” Roth has made little if any good movies (Hostel, anyone?)—which makes Knock Knock all the more surprising. Entertaining and fun to watch, the movie marks Keanu Reeve’s second solid entry in as many years (if you haven’t seen John Wick, see John Wick).

Too bad the ending sucks.

Knock Knock is your typical B-grade thriller, but Reeves is good in the lead and Lorenza Izzo and Ana de Armas do crazy well. The movie follows a formula seen before—a husband and family man makes a mistake one night, and that mistake comes back to haunt him—but the formula is well executed. Roth is surprisingly restrained; he lets the story play out organically rather than jumping into the action too soon. The movie isn’t particularly suspenseful, but it’s fun nonetheless.

Sadly, the movie ends with a fizzle. The climax is underwhelming at best, a shrug-inducing conclusion that makes you say, “Really?” The ending could have been worse, but it could have been a whole lot better.

Knock Knock is a fun little thriller—especially if you like hot, crazy chicks—but its ending keeps it from being anything of real significance.

Review by Erik Samdahl. Erik is a marketing and technology executive by day, avid movie lover by night. He is a member of the Seattle Film Critics Society.