10 Cloverfield Lane is a tension-filled thriller that’s worthy of the secrecy surrounding it

John Goodman and Mary Elizabeth Winstead are terrific in this nervy little movie.

10 Cloverfield Lane is the first big movie surprise of the year.

And by that, I don't mean it's unexpectedly good (although it is very, very good), or that it does things you wouldn't expect, or anything like that. I mean that up until January, even the most dedicated of movie fans didn't know it existed.

Producer J.J. Abrams so successfully hid the production of this spiritual successor to his 2008 found-footage monster movie Cloverfield (it has nothing to do with its predecessor; think of the two Cloverfield movies as an anthology film franchise akin to television's The Twilight Zone) that when it was first announced via a trailer on January 13, moviegoers only had to wait eight weeks before it debuted.

That kind of secrecy is all but impossible to pull off in 2016, and the excitement of somebody actually doing so has resulted in 10 Cloverfield Lane drawing all sorts of buzz. What is this thing? How did we not know about it? (Rolling Stone's David Ehrlich can help answer that latter question.)

None of this would matter if the movie stank, but 10 Cloverfield Lane is a taut little thriller that reminded me of last year's Ex Machina — though it's a bit pulpier and goofier than that sci-fi drama. It traps three characters together in a bunker, then heavily suggests the world outside has ended. But our point-of-view character doesn't know for sure that the world has ended (and neither do we), which leads to an increasingly tense standoff. Has she merely been kidnapped?

The ways in which 10 Cloverfield Lane twists and inverts that question end up being a big part of the fun, so I'll tread lightly with spoilers.

But here are five reasons the film justifies all that breathless secrecy.

1) The premise is simple but incredibly elastic

10 Cloverfield Lane opens with a young woman named Michelle (Mary Elizabeth Winstead) fleeing a crumbling relationship. We don't know why she's leaving, nor what she and her fiancé argued about, only that she's in a hurry. And then, just outside of town, she's in a car crash.

When she wakes up, she's in a bunker with a grizzled survivalist named Howard (John Goodman) and a guy about her age named Emmett (John Gallagher Jr.). Howard insists that the end of the world has come and that he's saved both Michelle and Emmett's lives. Why can't they just be a little grateful?

Of course, because Michelle was apparently unconscious for the so-called apocalypse, she can't know the world is over. And the film dangles tantalizing clues that both support and refute Howard's claims throughout its 100-minute running time. Is that a car Michelle hears above her room in the bunker? If so, then why are there no signals coming through on Howard's emergency radio?

The result is a thriller that boasts a deeper character study at its core. When we first meet Michelle, she's presented as someone who bails when things get tough; what happens when she can't bail any longer? And if Howard is someone who hides away from terrible things, what happens when he can no longer hide from the terrible things he himself may have done?

10 Cloverfield Lane turns what's essentially a stage play or TV bottle episode into an endlessly nerve-rattling experience that could only be had in a movie theater. That's thanks to...

2) First-time director Dan Trachtenberg is expert at building tension

If you're at all familiar with Dan Trachtenberg, it's for a short fan film he made a few years ago; it's based on the video game Portal, and it was a hit on the internet. Other than that, he hasn't directed a feature film or anything of that nature. So it's a big sign of faith that his first film is something this prominent, even if the film's budget and scope are ultimately pretty small.

But Trachtenberg skillfully and subtly builds out the horrors of both the bunker and whatever is happening in the outside world. There are some terrifically creepy moments peppered throughout the film, and Trachtenberg shoots Goodman as a looming, powerful presence, someone who sees you when you're sleeping and knows when you're awake.

He's also great at showing how Michelle goes from wanting nothing more than to leave the bunker to slowly accepting it as her new normal. At first, he shows her in lots of shots where she's the only character, but as her stay continues, she slowly lets Emmett and Howard into the frame with her. As Michelle — and Trachtenberg — come to accept her situation, it allows the film to pull more rugs out from under us.

3) The film makes beautiful use of its cast

Hollywood hasn't entirely figured out what to do with Winstead over the years. She's a very physical actor, conveying so much about her characters through her posture and body language; at times, she's brought to mind a young Sigourney Weaver, even as the films she's appeared in have crumbled around her.

10 Cloverfield Lane is the star vehicle Winstead has been waiting for. She barely speaks for the film's first half-hour, but she conveys both Michelle's careful strategizing and her gradual acceptance of her situation entirely through how she moves in the frame. Michelle is the hardest type of character to pull off in a traditionally structured screenplay — a super-smart hero who is always one step ahead of the audience. Winstead makes her someone who keeps you guessing.

Goodman is her terrifying opposite, a guy who pretends to put all his cards on the table but who's clearly hiding an entirely separate deck in his pocket. He's been heading toward his first Oscar nomination for a while now (he was in two Best Picture winners in a row, with 2011's The Artist and 2012's Argo), and it would be terrifically apt if he received one for his creepily nuanced work here.

4) The screenplay keeps you off-balance

The first thing Michelle would probably do is make a break for it, right? Well, 10 Cloverfield Lane's script (by Josh Campbell, Matthew Stuecken, and Whiplash director Damien Chazelle) has her attempt that escape at the earliest possible opportunity — and lets her learn some valuable information about whether Howard is telling the truth along the way.

It's just one of the smart ways the film throws viewers off-kilter. The screenplay keeps doling out new information, but actual answers are scarce. By the end, you will know the basics of what happened down in the bunker and up on the Earth's surface, but there will be many smaller mysteries worth pondering, perfect for viewers to argue about on the way home.

Some people will see this as a demerit, but I would argue it plays to one of the film's strengths. How much do you really know about the people you live with? Certainly, 10 Cloverfield Lane amps up that question by imprisoning Michelle with two strangers. But the same feeling of uncertainty is applicable to the man she was going to marry; she obviously had questions about him that ultimately made her run.

5) 10 Cloverfield Lane's third act is at once hugely flawed and incredibly entertaining

Major, major spoilers follow. Don't read on if you don't want to know.

At film's end, Michelle finally makes her escape, using everything from a shower curtain to a barrel of acid. (Trust me, it will make sense.) Once she makes it above ground, everything seems fine. The air is even breathable. She's been lied to, and Howard somehow staged all of the chaotic stuff she saw from the tiny window in the bunker door earlier in the film.

Oh, except there are aliens. Yes, real aliens, patrolling the fields surrounding Howard's farm. And Michelle eventually has to destroy an alien spacecraft, armed with only a cigarette lighter and a bottle of whiskey. (Yes, it's like a slightly more plausible Independence Day.)

If anyone has complaints about 10 Cloverfield Lane, they'll stem from its ending. And I'll admit that "It's aliens!" is one of the less appealing answers to just what's really going on that the writers could have come up with. From the second Howard mentions, early on, that he suspects the US was attacked by either the "Russkies" or something extraterrestrial in origin, your mind will gravitate toward the latter, because it's always aliens. Plus, Trachtenberg isn't as sure-footed when it comes time to mount some alien-destroying spectacle and lean on some shoddy computer effects.

But at the same time, by the time you find out the truth, 10 Cloverfield Lane has spent quite a bit of time arguing that the best way to deal with problems isn't to run from them (as Michelle does) or to hide away from them (as Howard does), but to face them head-on. In order for Michelle to finally resolve the crisis that opened the film — her frayed relationship — she has to face down her metaphorical demons, even if they're in a UFO. It's a conclusion that won't be to everyone's liking, but I can't fault a climax this weird when it produces a final shot as perfect as 10 Cloverfield Lane's — though you'll have to go see the movie to find out what it is.

10 Cloverfield Lane is playing throughout the country.