From left, Michael Shannon,Charlie Tahan, and Samantha Morton in The Harvest (IFC Films)

Parents just want what’s best for their children, don’t they? Such is the thinking of Katherine and Robert (Samantha Morton and Michael Shannon) regarding their young son Andy (Charlie Tahan), who seems to be unable to walk and is generally a very sickly kid. The family lives in a fairly isolated rural area, but there’s a young neighbor, Maryann (Natasha Calis, The Possession), who has recently moved in with her grandparents after the death of her father. The girl’s curious about Andy, and the two strike up a friendship. This doesn’t sit well with the suspicious Katherine. Robert doesn’t see much wrong with the kids being together, but Katherine reveals the bigger problem to Maryann’s grandparents: Andy is dying, so it wouldn’t be best for Maryann to get too attached to him.

But wait, you may be asking, is this an IFC Midnight film, directed by John McNaughton, who once brought us edgy, true-blue midnight films like Henry: Portrait of a Serial Killer and later Wild Things? At first, The Harvest seems to be a left turn of a comeback, without a trace of the dark or salaciousness that one saw in his more well-known work.

This new film sounds like a soapy melodrama. Indeed, for the first half, it kind of is. It’s a welcome surprise to see McNaughton back to work in films again and that he has made a sensitively presented drama. (It’s been almost 15 years since his last feature.) This could be almost a movie for children with its focus on two young souls trying to form a bond involving catch and Xbox games. Morton plays the mother as headstrong but concerned for her son, with Shannon as the husband and father caught in the middle.

Then the second half comes around, wherein Maryann hides in the house—she can’t let Andy’s mother find her after all—and she discovers the secret in the basement Katherine and Robert have apparently been hiding extremely well. It’s from here that the movie becomes much weirder and darker. Also, there are more plot holes that develop, popping up like a bad rash.

Much of what happens could be solved by a simple call to the police. Why this happens isn’t quite clear, despite Maryann seeming to be a smart enough character. What’s curious is how Morton’s Katherine just goes into super-over-the-top mode, as if McNaughton remembered what kind of filmmaker he is after 50 minutes of making a subtle and delicate tale of lost children.

Morton contributes to the tonal inconsistency of the film. In the first half, she plays the stern mother well before turning into a crazy-B-word of a maniac—where are the wire hangers when you need ’em—and the movie becomes funnier than actually being scary. Of all people, Shannon is actually the winner here as far as the acting goes, given how manic he often is in other films. Luckily, he has the meatiest character to work with, full of turmoil about what he’s doing and the secrets he’s been covering up for so long. Compared to Morton, he’s subtle, which is still scary to see.

The kid actors fair as best as they can, given the circumstances. Tahan has to play a lot of melodrama, and he tries to match the script’s batty demands, while Calis has mostly one mode to play throughout: hey, adults—yeah you, grandpa (Peter Fonda, kind of wasted here)—why don’t you believe me? HELLO?!

By the time the film arrives to the intense thrills of the climax, it becomes tasteless fun, but the whole experience is a weird sit. The Harvest does so much at first to establish its characters in a “real” movie, with stakes based in believable motivations and real-world, life-and-death concerns, that it forgets what is going to come, which is a trashy (almost) Lifetime movie about a psycho mother/wife and a hapless father/husband with two kids trying to get out of harm’s way. It has entertaining spurts because of how the adult actors commit to their roles, but it gets undermined by the extreme tonal shift.