Throughout his career, filmmaker Danny Boyle has taken chances. Some have worked ("Slumdog Millionaire," "Sunshine"), others have failed ("A Life Less Ordinary"), but he's remained a captivating, intrepid presence on the movie scene. "127 Hours" is perhaps his most astonishing work to date, bringing to the screen the staggeringly nightmarish true story of Aron Ralston, who found himself literally between a rock and a hard place as he fought for his life in the wilds of Utah for just over five days. It's just Boyle, star James Franco, and a canyon filled with anxiety and delirium for 90 extraordinarily compelling minutes.

A skilled hiker trekking through a gorgeous national park in Utah, Aron (James Franco, in a stupendous performance) is a man who craves his solitude, breaking away from friends and family to be the king of the wild, armed with his sharp directional instincts and basic tools of survival. After meeting and guiding two lost visitors (Kate Mara and Amber Tamblyn) to a hidden lake in the area, Aron speeds off to his next impossibly claustrophobic destination, only to meet a loose rock on the way, which sends him to the bottom of a canyon, pinning his arm against a wall. Unable to break free, Aron embarks on a turbulent psychological ride of despair and resignation, relying on his survival training to keep him alive. As the days pass, Aron grows more disoriented, confronted with his sin of isolation while facing one last gruesome shot at personal freedom.

While "Slumdog Millionaire" pursued a more romanticized depiction of fate, "127 Hours" brings Boyle back down to Earth. This is a harrowing, trembling story of endurance, with a full commitment made to Aron's most primal urges and thoughts during his near-weeklong ordeal. Fearlessly, Boyle plunges into the mix, depicting Aron's struggle through a complex series of edits and cameras, reflecting the man's own multi-media coverage of his misfortune, providing a scattered, intimate grip of the situation. Boyle loves to splash the screen with visual flair, and while a few sequences are overcooked with artificial prodding, the majority of the film creates a visceral, insightful experience, putting the viewer inside the claustrophobic head of a man who cannot move, trapped in a place others would fear to tread (making rescue impossible). Sustaining despair is not an option here, and Boyle urges the film to a ripe, assured tempo through bold cinematographic choices and a rumbling series of jubilant soundtrack cuts.

Aron is no ordinary man. Though faced with a crushing reality of death, Aron's also a realist of sorts, quickly springing into action once the initial shock of his pinned arm wears off, taking note of supplies and rationing what little water he has left. While still vulnerable, Aron's command of stamina provides a nice twist to the picture, with overconfidence, not mortal fear, his critical weakness. As time drips along, the trapped man slowly comes to regret his antisocial behavior, wishing at the hour of his impending death that he should've spent more time with loved ones, with images from his past rushing through his weary, hallucinating mind. It's a spectacular message of communal importance from an unlikely source, placing emphasis on the crowded euphoria of life. If "127 Hours" didn't descend into eye-popping grisliness, it would likely be the feel-good movie of the year.

After a few days slowly dying of thirst and dementia, saying his goodbyes to a video camera, Aron comes to a realization: to free himself from the rock, he must cut his arm off. Equipped with a dull blade found in a dollar-store toolkit, Aron digs in for the fight of his life and Boyle soaks up every single step of the impromptu surgery. It's a gruesome, genuine scene of limb removal, sacrifice, and ungodly amounts of pain, with special industrial stings on the soundtrack to reinforce the tendon slicing. The faint of heart will likely explode, gorehounds will be fascinated by such a seamless special effect, and Boyle fans will once again rejoice in the presence of a filmmaker who refuses to step away from the primal requirements of salvation.

It goes without saying that "127 Hours" is a challenging picture to sit through. The brave are rewarded with a bold, unflinching depiction of perseverance, eased along with a potent display of domestic deliverance, making the feature worth enduring the dizzying displays of courageous self-sacrifice.