Dating back to biblical times, the word, "babel," can be defined as "a confusion of sounds and noises." This is a crucial detail not to be overlooked in "Babel," a dramatically arresting and thematically intoxicating drama circling around four groups of characters over three continents who are all fundamentally linked by a deadly rifle. That gun, however, which sets off a chain reaction forever altering the lives of its characters, is really only a plot device. What director Alejandro González Iñárritu and screenwriter Guillermo Arriaga (2003's "21 Grams") are more interested in exploring is the core breakdown of communication between people in a fast-moving world that barely slows down long enough to hear what each other are saying. For some, it is a basic language barrier that creates conflict at critical times, while for others it is the lack of emotional understanding between everyone from family members to sexual partners that creates the issue. If the characters populating the world of "Babel" could only learn to listen to each other, they would unequivocally be a lot better off.

When a Moroccan father (Mustapha Rachidi) sends sons Yussef (Boubker Ait El Caid) and Ahmed (Said Tarchani) out to hunt for jackals with a rifle he has recently been given, he has no possible way of predicting the downward spiral this causes. Believing that the gun hasn't any power or vitality, Yussef aims at a faraway charter bus making its way through the mountains and fires, accidentally hitting American tourist Susan (Cate Blanchett) in the process. Desperate to find help for his critically wounded wife but hours away from the nearest hospital, Richard (Brad Pitt) places his bets on a tiny nearby town where he hopes the resident doctor might be able to help. Across the water and into the suburbs of San Diego, typically dutiful nanny Amelia (Adriana Barraza) has no one to watch her young charges Debbie (Elle Fanning) and Mike (Nathan Gamble) on the day of her son's wedding, so she wrongfully decides to take them with her across the Mexican border. Meanwhile on the opposite side of the globe, deaf-mute teenager Chieko (Rinko Kikuchi) is set adrift among the skyscrapers, neon and club spots of Tokyo as her relationship with her widowed father (Koji Yakusho) breaks down and her yearning for attention and acceptance scales to new heights through increasingly radical sexual and rebellious behavior.

Thought-provoking long after its haunting final frame, "Babel" is a weighty and complex spellbinder. Using a similar non-chronological framework as his previous two films, 2001's "Amores Perros" and 2003's "21 Grams," director Alejandro González Iñárritu cross-connects four separate story threads in obvious and not-so-obvious ways, each one bound by the rifle that connects them and the miscommunication that ultimately tears them apart. Interweaving a large ensemble of characters isn't an easy task—too often some of the stories and people get lost in the shuffle and feel extraneous to the central thematic conceits—but "Babel" does an exquisite job of handing out equal screen time for all and making sure that every moment holds a purpose in the grand scheme of things.

For American vacationers Richard and Susan, whose marriage and very lives have begun to unravel since the sudden death of their infant son, it takes a possibly tragic shooting accident to give them the chance to put things in perspective and find redemption in each other before it is too late. As Richard desperately seeks to find medical help in a desolate Third World landscape and Susan's condition worsens with each minute, their perilous predicament and ultimate journey toward reconciliation is touchingly and believably pulled off by the delicate touch of Iñárritu's filmmaking prowess and the committed performances from Brad Pitt (2005's "Mr. & Mrs. Smith") and Cate Blanchett (2004's "The Aviator"). For Pitt, this is courageous turn in the way he allows the camera to show his ripening age—he's 42—and the vulnerability of a man faced with the prospect of losing his wife in an inexplicable occurrence. Blanchett has an even more difficult assignment; laid up for most of the film and in great distress, the actress nonetheless finds a way to reveal the depths of empathy within Susan without any information about her having to be spelled out.

Faced with the knowledge that they have hurt and maybe even killed an innocent bystander with the gun their father has entrusted them with, brothers Yussef and Ahmed are racked with guilt and, as children would most likely do in such a situation, try to cloak their misdeed from their dad out of fear and shame. Aided by a memorably nuanced and naturalistic performance from newcomer Boubker Ait El Caid, as triggerboy Yussef, this section of the picture culminates in a devastating, nerve-wrangling way that is impossible to predict. Snapshots of this lower-class family's life—they gather around and share a plate of food for dinner; Yussef is found to be guilty of regularly peeping at his nude sister—do not directly relate to the main plot, but they do serve to bring reality to the particular socioeconomic squalor of their lifestyle and deepen the notion of familial disconnect.

With their parents out of the country and no one to care for them, nanny Amelia's decision to drag American siblings Debbie and Mike along with her and grown nephew Santiago (Gael García Bernal) to a Mexico wedding leads to a disastrous run-in with border cops. Save for the kids, all involved are to blame for what happens next. Amelia risks the trust of Debbie's and Mike's parents, the lives of the children she has cared for all their lives, and even deportation. Santiago is at fault for his erratic behavior and drunken driving when the border patrol cast suspicions upon them. And the cops are torn between their duties as law enforcers and their inability (or is it unwillingness?) to understand Amelia's plight. Mexican actress Adriana Barraza is superb at playing both warmth and hopelessness as Amelia; although she has made a number of mistakes, the audience cannot help but side with her point-of-view and involve themselves in her fight to make a right out of a wrong.

The storyline with the biggest impact is, coincidentally, the one that would seem at first to have the least amount to do with the Morocco and Mexico/America scenes. In fact, it actually is the most eye-opening of the bunch in its portrayal of a young woman drowned by a world that cannot understand her. Deaf and mute, teenage schoolgirl Chieko wants nothing more than to be accepted by her hearing peers, but the boundary between them, not to mention the one between she and her father, leaves her feeling empty and alone. In retaliation, Chieko flirts with sexual exhibitionism while numbing herself to the memory of her mother's suspicious death. In one of the strongest acting jobs of the entire year, Japanese performer Rinko Kikuchi is a heartbreaking standout as Chieko. Multilayered and consistently fascinating to watch, Kukuchi is able to show a spectrum of emotions and a lost soul underneath her exterior without speaking a word of dialogue in the film. The ways in which director Iñárritu conveys Chieko's deafness are ace, as in an unforgettably edited and scored sequence where she goes to a rave with some guys she barely knows and is at a complete loss in understanding what music is and why everyone around her is jumping around. The use of Earth, Wind and Fire's "September" in this scene, the song pulsating with energy and then abruptly dropping out over and over again, slides the viewer directly into the skin and mindset of what it must be like to be deaf.

"Babel" ends on a note of redemptive power that brings hope to the idea that we as human beings still have the capacity to feel for each other and bond on an interpersonal level even with the most indomitable of odds stacked against us. Still, nothing is tied up in a neat bow and there are a handful of loose plot elements left hanging that aren't utterly satisfying—that is, until one exits the theater and comes to grips with the meaning behind the film's fractured storytelling. The important things in "Babel" do not necessarily lie in their final destinations, but in the tricky, unpredictable paths leading to these points. Some characters are left for the better, while others are for the worse, but they are all united by one imperative characteristic: their own painful, aching, transformative humanity.