A number of much-anticipated films had buzz-generating premieres at the 2015 Toronto International Film Festival, including Ridley Scott's The Martian, Tom McCarthy's Spotlight, Tom Hooper's The Danish Girl, Paolo Sorrentino's Youth, Jay Roach's Trumbo, David Gordon Green's Our Brand Is Crisis, Cary Fukunaga's Beasts of No Nation, and Charlie Kaufman's Anomalisa. And yet, the major prize at the annual September event, considered in recent years a starting line for the Academy Awards race, did not go to any of these big name movies, but to Room, a low-budget American drama from Irish director Lenny Abrahamson and, making her film debut with an adaptation of her 2010 novel, Irish-Canadian author Emma Donoghue.

Not to be confused with Tommy Wiseau's so terrible it's amazing 2003 disaster The Room, this film opens with Joy Newsome (Brie Larson) celebrating the fifth birthday of her son Jack (Jacob Tremblay). The two are living very simply in the squalor of a tiny 10' x 10' room. Ma makes Jack a small cake using what few ingredients there are in this stifling small space. We come to understand why this mother and son are calling these cramped, dingy quarters their home. At 17, Joy agreed to help a stranger who claimed he had a sick dog. It was a trap and in the seven years since then, this young woman has been living locked in this unknown garden shed. Her captor, Old Nick (Sean Bridgers), pops in nightly for sex while Jack sleeps, or doesn't, inside a wardrobe. Nick brings a few essential items for his captive and the rarely-seen child he had with her. He expects gratitude for his grocery store runs, as if he wasn't keeping these two humans against their will in a code-protected, soundproof shed.

Mother hatches an escape plan that hinges largely on her son's ability to play sick and then dead. While this seems like a spoiler, it occurs early enough to necessitate being revealed. The movie does venture outside that titular domain, following Jack in a breathtaking, pulse-pounding sequence that feels too good to be true. It is not a dream, though, instead bringing the movie and this family's life into a new phase.

Room is as interested in what comes next for Joy and Jack as it was in this horrific predicament they found themselves in for several years. It becomes a different movie after it escapes those confines, but not a lesser one. Though it loosens the grip of that riveting first half, it remains thoughtful and interesting.

Much of the film's power is the direct result of the two actors who carry it: Larson, who received raves and a Best Actress nomination from my Online Film Critics Society for her turn in 2013's Short Term 12, and young relative newcomer Tremblay, who spends most of the film with a lush ponytail. Larson, who broke into film in 2004 after five years as a tweenaged TV actor, surely has her choice of bigger studio movies. Her past credits include 21 Jump Street and Scott Pilgrim vs. the World. While she isn't turning all of those down (she appears in Trainwreck, for instance and is now shooting the 2017 big budget prequel Kong: Skull Island), she does seem to be drawn to roles and films of substance. Joy and Room certainly fit the bill.

Larson bares her soul to convey the torment of this character. She wears make-up in just a single scene and it stands out. Most of the time, she looks beaten down by the world and on the verge of a breakdown. Keeping her going is her son, who Tremblay ensures is an appealingly real child and not just some stage mom's kid being precocious. Having spent his first five years in that cell with a skylight, Jack struggles to understand the difference between reality and what he sees on television. It's a terrifying foundation for a young life and the effects of that situation linger even when he has medical care, a warm bed, and new toys.

Among recent films, Room reminds me most of David Fincher's masterful mystery Gone Girl. While that was driven more by a twisty plot and a strained romance, this is more invested in these two tortured characters who have been each other's only ally for years in captivity. You can question the tidiness and believability of the actions that cause the movie to shift gears. You can also raise questions about the film's embodiment of evil and how he can do what he does so long without detection. Of course, similar atrocities have occurred in real life, so consider that before starting your kneejerk contrarian thread on IMDb's message boards for the film.

Any concerns regarding the film, from the inexplicably creepy vibes emitted by Joy's stepfather (Tom McCamus) to the seeming ease with which this years-long problem is resolved, are minor when weighed against the film's powerful, thought-provoking core. A lesser movie would have ended with an escape, but Room finds intriguing, believable misery awaiting mother and son on the other side. Life wouldn't just conveniently return to sunshine and rainbows with hugs from family members unseen in years. Some may argue that Room belabors this point or that it struggles to transition from one setting to the other. You can nitpick anything, but the fact remains that Donoghue, Abrahamson, Larson, and Tremblay have made something resonant and meaningful in a way that few films are.

The public's vote in Toronto has been echoed by critics, who have been lavishing the film with high praise ever since. If nominations and awards were won simply by critical approval, Room would be sitting pretty right now. But those honors are given out following long, expensive strategic campaigns. Room has a few factors working against it, such as the fact that its young distributor, A24 Films, has been outright ignored by major awards despite strong reviews. The studio has also repeatedly struggled to find audiences, despite the high quality of their output. No fewer than four of 2015's best films hail from A24, but you're mistaken if you think Ex Machina, While We're Young, and The End of the Tour have any chance of snagging an Oscar or even Golden Globe nod. Room's prospects are a little better, due to its timing. There is also the fact that Larson did not receive major accolades for Short Term 12, giving her as much of an overdue vibe as a just-turned-26-year-old actress can develop. If the public embraces Room even to a modest degree, that will help the film try to overcome the long odds of making an awards season run without the backing of a major, established studio.

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