There are plenty of obvious reasons to praise the film — chief among them Brie Larson's standout performance as a young kidnapped woman — but the reason it works at all is thanks to a very careful choice to translate the novel's structure almost literally to film.
Yes, incidents from the book have been left out here and there, but by and large, the film captures the book's spirit. How does it do that? By making sure we never see anything we're not supposed to.
Room uses first person in a way that could be tricky on screen
On the page, Room is told from the point of view of a young boy named Jack, who lives in a confined space he calls, well, "Room." For Jack, who's turning 5 as the film begins, Room is his entire world and Ma (Larson) his only companion.
The reader, of course, can suspect what's going on here. It's pretty clear from very early on that Ma was kidnapped as a teenager by the man Jack calls "Old Nick," and then kept in this tiny space where he repeatedly raped and assaulted her.
But Jack is 5. He doesn't understand most — if any — of this. It's tricky enough for Ma to get him to comprehend that there is a world beyond Room, filled with all sorts of things he's only seen on TV. Imagine how hard it would be to go from there to trying to execute some sort of escape plan, with your son as the linchpin. Yet that's what much of Room is about.
The problem becomes how to depict that on film. It's easy to leave stuff to the imagination in a book. That's literally how the form works. But film has a tendency to literalize, to flatten out, to reveal what's happening off the page just as easily as it reveals what's happening on it.
For another example of this from a much more popular series, consider the first two Harry Potter films, which are the weakest films in that series. Adapted incredibly faithfully from the books by screenwriter Steve Kloves and director Chris Columbus, they reveal something that was always lurking within J.K. Rowling's books but is much easier to miss in novel form: Harry doesn't really do anything. He's the point-of-view character, and thus, the first two books use him as a conduit to get across a lot of crazy information and adventures. But when it comes to being an active participant in his world, he leaves that to his super-smart pal Hermione. Future films made subtle tweaks to Rowling's narrative to make Harry more active as a protagonist, and as he grew up, he trended in that direction anyway.
By default, the literal point-of-view character in a film is the camera. It controls what we see and don't see. It controls the characters in charge of the story. And it controls how we interpret the information we're given. This means the perspective of a film is almost always filtered via the sensibility of the director, who controls that camera.
So how do you adapt Room, when you know the camera is going to immediately make the horrifying realities of Ma and Jack's situation all the more real for viewers? You play little tricks.
How Room keeps you from dwelling on its horrors
Some of these tricks are obvious ones you've likely already thought of. The action of Room, for instance, is confined entirely to things that Jack is able to see or hear, save for its very, very last shot.
He might only be present in the room to overhear a conversation, or he might catch a glimpse of Old Nick through the slats in the closet where he hides when the man comes to visit. But if he's not there, we don't get to see what's happening. This fully grounds the film in his perspective.
Some of these tricks are so obvious as to be clichéd, but they work well here. Donoghue, who wrote the script for the film, has given Jack a smattering of voiceover lines here and there. While this device could feel too precious, Donoghue and especially young Jacob Tremblay give him a voice that's authentically childlike while also giving viewers a window into the horrors his mother has faced, as filtered through his point of view.
But there are other, subtler tricks that director Lenny Abrahamson uses to orient viewers to Jack's vantage point. The camera ably captures just how vast Room can feel to such a small child, using tricks of focus and perspective to make what's ultimately a small garden shed feel like it contains whole planets. Yet he also uses the skylight that lets in a little patch of blue sky every day to remind viewers that Jack doesn't realize everything he's missing out on, trapped in the little shed.
Similarly, the film's editing ably establishes the routine of life in Room, the way the days bleed into each other. That doesn't impact Jack so much. He's a kid and, thus, able to bounce back. But it wears on his mother, who doesn't know how much more she can take. And with all of those filmmaking tricks thus established, Abrahamson can subtly start switching them up when it's time for things to change.
Where Room falls short
Some spoilers follow.
Room was a popular enough book, and the film's marketing has done a good enough job of letting viewers know about what happens at the movie's midpoint that I feel comfortable saying that Jack and Ma eventually make it out of Room. The high point of the film is Jack's escape into the wide world, seeing the big, blue sky stretching out over his head and being briefly stunned by it, even as he's supposed to be on the run from Old Nick, looking for help.
What's slightly amazing is how much tension Abrahamson and Donoghue wring from a situation that can only end one way if there's going to be more movie. (If Old Nick catches Jack, then it's highly unlikely he and Ma will continue to live.) But what's also impressive is how Abrahamson uses some of the same techniques he used in Room to make the wider world feel almost as small as that shed. He rarely leaves interior spaces, choosing to save the great outdoors for moments of particular importance.
But this is also where the film struggles a bit, because it remains in Jack's point of view, while wanting to convey what his mother is going through in ways both subtle and not so subtle. That leaves the film sometimes working at cross-purposes, with some elements reflecting Jack's state of mind and some reflecting Ma's.
This is particularly true of the far-too-overdramatic score. The final shot of the film is scored to a piece of music that sounds like it should soundtrack Moses leading the Israelites across the Red Sea, not the conclusion of an intimate character thriller. Larson's performance is so good (and so transformative) that we don't really need the constant cues as to her emotional state.
This is not to say that Room has a failure of nerve or anything like that. It has admirable focus and restraint. But it also badly wants to make sure viewers feel all the right things, precisely when the stunning work of its lead actress and actor should be more than enough. You'll find far more understanding of the crushing weight of trauma in Larson's micro-expressions than in that score or in some of the more manipulative shots and moments in the film's final half hour.
But Room is also a tremendous achievement, even when it can't help itself from going too far. It's tough to plant the camera in a very specific point of view, and then actually follow through. That Room succeeds is admirable. That it manages to tell a gripping, involving, moving story in the meantime is the icing on the cake.
Room is playing in limited release. It will expand throughout the country in the weeks to come.