The keys to a good mainstream horror movie are a semi-original premise, at least three really good jump scares, and a strong performance from the lead actor/actress. Smile has all of those things. You also have to love the ingenuity of turning a mundane act into nightmare fuel. Here's a film that makes smiling feel like a sinister function. Not an easy task!

Rose Cotter (Sosie Bacon) is a doctor in an emergency psychiatric facility. She has a tendency to overwork herself, despite the pleas from her supervisor (Kal Penn) to go home and rest. One day, a young woman named Laura Weaver (Caitlin Stasey) is brought in, claiming that a weird, smiling entity has been coming after her. The women talk, but then Laura abruptly kills herself in front of Rose. In the days that follow, Rose begins experiencing strange hallucinations in which, among other things, people around her begin getting weird, evil-looking smiles on their faces. She's been infected by whatever was terrorizing her patient.

Now the shoe is on the opposite foot. Rose begins looking crazy to her fiancée (Jesse T. Usher), her sister (Gillian Zinser), her therapist (Robin Weigert), and Joel (Kyle Gallner), the cop ex-boyfriend investigating Laura's death. They all believe the trauma of witnessing a suicide is triggering Rose's own traumatic past. Of course, that's not true, because the movie would have nowhere to go if it was. Joel eventually agrees to help her, and they uncover a shocking chain of events, along with a possible, if unpleasant, way for her to rid herself of the torment.

Smile has a great tone. Director Parker Finn, making an impressive feature debut, pulls out jump scares where you least expect them. They're legitimately surprising, as opposed to just a startle reflex from having an abrupt loud noise on the soundtrack. Other moments are unsettlingly eerie. There's a scene at a birthday party that sent a chill up my spine. (Kudos to Matthew Lamb, the child actor who beautifully sells that moment.) Finn has additionally cast the film with actors who know how to smile in a creepy fashion. The importance of that is impossible to overstate. The premise could be silly were it not for performers who can carry it off.

Beyond that, the movie is notable for trying to do more than just scare us. Smile deals smartly with two things – mental health and trauma. Several characters make offhand derogatory comments about Rose's patients, calling them “headcases” or “crazies.” People close to her change how they react once they think she's having issues of her own. That speaks to the marginalization of the mentally ill in society. The entity, meanwhile, feeds off its victims' trauma. At some level, the story is a metaphor for the emotional anguish trauma causes. Once you've gone through a profoundly troubling event, the impact stays with you, causing more problems like anxiety or depression. Plenty of horror movies have used trauma as a device; this one goes deeper.

Sosie Bacon glues the horror together with a performance that nicely conveys the panic Rose is enduring. We consequently care about what happens to her. Bacon ratchets it up little by little as the movie progresses, never going over the top. Since her work feels dramatically authentic, the plot's trauma-related theme fully sinks in. Gallner is well cast, too, avoiding the usual “horror movie cop” clichés to make us believe that Joel believes Rose.

Smile doesn't quite have the perpetual sense of underlying dread that The Ring, which it resembles in a couple respects, had, and a dream sequence about two-thirds of the way through goes a bit too broad. Otherwise, this is a pleasingly creepy horror flick that opens the obligatory door for a sequel, yet does it in a manner that isn't cheap. You may not feel like having anyone smile at you for a few days after seeing the movie.

out of four

Smile is rated R for strong violent content and grisly images, and language. The running time is 1 hour and 55 minutes.