“Moonlight” has two 13-year-olds doin’ it, makes frequent references to the girl’s recently begun menstrual cycle, and includes a scene where the boy craps his pants and the girl has to clean him up. Wanna guess which continent the movie comes from? That’s right! Europe! (That’s because it’s a drama. If it were comedy, it would be American.)

Dutch director Paula van der Oest follows up her much-admired “Zus and Zo” with this moody suspense drama in which a young drug mule (Hunter Bussemaker) of vaguely Middle-Eastern origin is shot and left for dead in the woods of Belgium. He stumbles into a backyard shed belonging to a wealthy couple (he’s a psychiatrist, she’s a concert pianist), where the pair’s bored daughter Claire (Laurien Van den Broeck) finds him and, her mother instincts and sexual curiosity both beginning to bloom, nurses him back to health.

Well, not entirely to health. He has been shot, for heaven’s sake. But she nurses him toward the direction of health, and though she doesn’t speak whatever his native tongue is and he doesn’t speak any of the several she knows (she uses mostly English), they develop a bond of friendship and childish affection.

Meanwhile, one of the boy’s pursuers starts nosing around the place, apparently seeking to finish the job of killing poor What’s-His-Name. To further complicate matters, Claire’s parents announce they’ve sold the house and are moving into the city, and that Claire should clear out anything she has stored in the shed, including whatever half-dead incontinent early-adolescent Arab boys she may have accumulated.

A question is immediately raised in the viewer’s mind, particularly if the viewer is me: Why doesn’t Claire go straight to her parents when she finds the boy? He would get the medical attention he needs, and surely Claire’s folks would see to it that he gets proper foster care afterward, if returning home is not an option.

Whatever the reason, she keeps him a secret and ultimately goes on the lam with him. The film takes on an odd, Dickens-meets-Fellini quality at that point, with chapters that could be called “Claire and the Boy Stow Away on a Catholic Youth Retreat, Where the Boy Must Pretend to Be Both a) Female and b) Mentally Handicapped” and “The Children Ingest Some of the Heroin That Came out of the Boy’s Butt.”

And yet despite those bizarre interludes, the film is quite serious about itself. Van der Oest keeps calling artful attention to motifs in Carel Donck’s screenplay like blood, sex and gender, but she never really DOES anything with them. Claire has her first period at the same time the boy is shot, and there are frequent allusions to the boy’s feminine appearance and frequent bleeding. There’s also the reverse, where Claire cuts her hair short to look more like him. But why? And so what?

I do like how the language barrier between the kids means they don’t speak much, and the film is often eerily quiet, to great effect. The gray skies of Europe give it a melancholy that underscores the children’s doomed mission. The situation compels you to keep watching, only to be disappointed when you realize the story’s not going anywhere.

C+ (1 hr., 26 min.; Not Rated, probably R for some violence, some creepy sexuality, some underage nudity.)