“Beast” is the kind of movie where, when a sexy stranger tells a woman he has just met that he’s “good with his hands,” you can bet he isn’t talking about carpentry.

Pascal, the hunky young man in question, is played by British actor Johnny Flynn with a smoldering, animal intensity that emanates from the screen like musk. In fact, after the film’s 27-year-old heroine, Moll (Jessie Buckley), has entered into a sexual relationship with Pascal, Moll tells him that the thing she likes best about him is his smell.

That isn’t a view shared by Moll’s imperious mother (Geraldine James), who turns up her nose at her daughter’s new boyfriend, as if he’s spent the night outside. It doesn’t help matters that there happens to be a serial killer at large who has been murdering young women on the picturesque English island of Jersey, and that Pascal — who has a criminal record, including statutory rape — has been investigated as a suspect.

The title of this moody feature debut by writer-director Michael Pearce is meant to highlight Pascal’s unsavory past, as well as to interrogate our assumptions about the working class. But Moll, who, as a teenager, once stabbed a schoolmate who had been bullying her, is no angel either. Despite singing in the church choir, she has a rebellious streak.

“Beast” sounds like a straightforward erotic mystery thriller, but that atmosphere is at times overshadowed by Pearce’s exploration of British classism, bullying and bigotry. There might be the whiff of the disreputable about Pascal, but he defends the weak and the bullied — or at least seems to. For much of the film, we waver between fearing that Moll has made the worst decision of her life and hoping the two of them run off together and live happily ever after.

Ultimately, there’s closure to that dilemma, but it’s probably not the ending you’d expect. Calling into question the very meaning of the film’s title, the climax of Pearce’s auspicious debut seems to come out of left field, but it makes a kind of perfect, if perverse, sense.