10 Cloverfield Lane is generally listed as a horror movie, and described as a sequel to Matt Reeves 2008 found-footage fright-fest Cloverfield. In fact, it’s neither. It’s not really a horror film, and it’s not remotely a sequel. Cloverfield had an urban setting, a young cast of terrified-out-of-their-minds millennials, and used the found-footage gimmick to build scares and thrills. This new film is something else entirely. It’s a powerfully suspenseful psychological drama, with a sci-fi twist at the end. Imagine Room set in the world of Independence Day, and you’ve just about got it.

Which leaves us with a powerfully engaging film with an essential weirdness that you don’t really notice until you leave the theater. It’s awfully well-acted though. And well enough written, aside from the fact that it doesn’t make a lick of sense.

The movie begins with a woman named Michelle (Mary Elizabeth Winstead), packing her stuff in a box, very emotional, leaving an apartment in a city. She finally walks out, leaving behind her room key and an engagement ring. All this is handled quickly, a fast-paced montage, no dialogue. She drives along lonely highways, and her phone keeps buzzing. She answers, and a male voice begs her to give him another chance. She disconnects the call without responding. Just about at the point when I thought ‘she’s paying too much attention to that phone to be able to drive safely,’ a truck smashes into her car, which careens off the highway. Blackout.

When she wakes up, she’s chained to a bed in a featureless concrete room, with an IV in her arm. Enter Howard (John Goodman). He’s not terribly communicative, but does explain that he saved her life, that she was in an accident, that he found her and brought her to his, well, shelter. Which she can never leave. Because something terrible has happened.

Howard is, we learn, a survivalist, and this shelter is his refuge from a disaster that he always anticipated, and which now has come. He’s not sure what the nature of that disaster might have been. He’s the kind of person who always anticipated catastrophe, and is a little jazzed now that one’s taken place. But what exactly is the problem? He doesn’t know, if the air outside is poisoned by chemicals or biological agents or aliens or radioactivity. But he’s sure that the area outside is uninhabitable. He shows Michelle the front door, up some stairs, and she can just barely see his livestock in a pen, two pigs, dead now of some dreadful skin disease. A woman comes to the door, her face ravaged as well, screaming to be allowed in, raw with disease, and then dies just outside.

There’s also a third person down there, a local guy, Emmett (John Gallagher Jr.), who helped Howard build the shelter, and was similarly rescued, though he did sustain what appears to be a major burn on his arm. Emmett’s clearly a few sandwiches shy of a picnic, but he’s the only potential ally Michelle might have. Assuming that Howard’s wrong, and they can actually escape. But who knows?

Because, of course, the central dramatic question in this film is ‘which is more dangerous, the world outside this shelter, or Howard.’ Because Howard is clearly crazy. And potentially lethal. And weird and creepy.

I mean, the shelter’s actually kind of nice. There’s a TV, not hooked up to any cable system or anything, but available for DVD and VHS movies, of which Howard has quite a collection (mostly of the John Hughes variety). There’s even a jukebox. There’s a kitchen, with electric stove, and plenty of victuals. And there’s plumbing, but that belongs more in the weird category.

Each of them has a personal space; Michelle has her featureless concrete room, Howard has a nice bedroom, and Emmett sleeps in the corner of a storage room. But the only bathroom facilities are in Howard’s room, and he insists on being present when Michelle uses those facilities. She does get a shower curtain to draw, for privacy. But she knows he’s right there. Which frankly creeps her out, and who can blame her? It is creepy.

So every plot twist has to do with Howard, some new revelation about him and what he stands for and what he intends. And, of course, there are twists and turns, moments when he seems genuine and decent, moments when he seems dangerously nuts. The entire film is a battle of wits, Michelle vs. Howard, with Emmett in the middle. In fact, I kept wondering if it wouldn’t make a better play than film.

You’d need three great actors; this film has them. John Goodman is genuinely one of the legendary American character actors ever, is he not? John Gallagher retains an air of mystery, and just a hint that this character may be brighter than he appears, that he’s hiding behind a clueless rube facade. And Mary Elizabeth Winstead is tremendous. I love the character’s intelligence, her wary vulnerability, the way the character plots and schemes and hides and thinks her way through problems. It’s a fine, nuanced performance. In an action thriller.

Why is Mary Elizabeth Winstead not a bigger star? She’s so good in Mercy Street, on PBS.  She was marvelous in Smashed, and in Scott Pilgrim vs. the World. Those are great movies, and she shines in them, but she’s also been charismatic and fun in crappy movies; a splendid Mary Todd Lincoln in Abraham Lincoln: Vampire Hunter. That’s a ridiculous film, of course, but she was honestly the best thing in it.

This is, of course, also kind of a ridiculous film, especially the last ten minutes, when something suggested by the ‘Cloverfield’ of its title happens. But it’s an acting tour-de-force, genuinely suspenseful and nicely directed, by first-timer, Dan Trachtenburg. It was such a pleasure to see a film that didn’t rely on gross-out bloodiness or cheap shocks, that instead just relied on two dangerous human beings, trying to figure each other out.