Halfway through his studies at the Central School of Speech and Drama in London, Bernal returned to Mexico to film "Amores Perros" for director Alejandro González Iñárritu. In this portrait of three different people brought together by a fatal car accident, Bernal played Octavio, a kid from a poor neighborhood who enters his Rottweiler in dogfights to raise money so he can run away with his pregnant sister-in-law. The film was nominated for a bevy of awards, including an Oscar for Best Foreign Film, and Bernal became an international star. He received plenty of media attention and offers for bigger budget films, but chose to continue his career in his native land.
His next big role came when director Alfonso Cuaron saw "Amores Perros" and offered Bernal one of two leads in the coming of age odyssey "Y Tu Mama Tambien (“And Your Mother Too”). The movie solidified Bernal as a serious actor and rising star, and the chemistry between him and co-star Luna carried the film—no surprise, since the two had been lifelong friends. On its surface, “Y Tu Mama” told the story of two adolescents on a road trip with an older woman (Maribel Verdu), but underneath the erotic romp was a story about the fragility of life and death, the gap between rich and poor. “Y Tu Mama” became an international hit, and won the Academy Award for Best Original Screenplay.
Bernal continued to accept challenging roles in Latin American films, starring as a priest in "The Crime of Father Amaro" (2002). Sent to assist an aging Father Benito, Father Amaro finds himself falling in love with a sixteen year-old girl. Torn between lust and devotion, he must summon the strength to choose the life he wants. The film was nominated for both an Oscar and a Golden Globe for Best Foreign Film despite mixed reviews. Meanwhile, Bernal starred as a young Argentine medical student, Ernesto Guevara de la Serna, who later became famed Cuban revolutionary Che Guevara, in “The Motorcycle Diaries” (2004). Along with Alberto Granado (Rodrigo de la Serna), Guevara embarks on a long and daring motorcycle trip, starting in Buenos Aries and traveling through Chile, across the Andes and into the Amazon. The two friends discover the real Latin America, thus igniting Guevara’s social consciousness. Once again, Bernal was in a film nominated for several awards, including a Golden Globe for Best Foreign Film. He also appeared in famed Spanish director Pedro Almodovar’s “Bad Education” (2004), playing several roles including an opportunistic actor and a drag queen.
Following his vamping performance in “Bad Education,” Bernal made his first English-language film, “The King” (2006), playing Elvis, a man discharged from the U.S. Navy who seeks out his estranged father (William Hurt) and winds up developing a relationship with his daughter (Pell James)—and Elvis’ half-sister—that allows him to infiltrate the family, unleashing epic violence and tragedy. In “The Science of Sleep” (2006), Michel Gondry’s bizarre sci-fi fantasy, Bernal was a shy and eccentric young man whose dreams are constantly invading his waking life. His confidence comes out, however, in his dreams where he’s the charismatic host of “Stephane TV.” But then he meets his neighbor, Stephanie (Charlotte Gainsbourg), with whom he develops a budding romance that finally awakens his sleeping confidence.
Bernal next reunited with Iñárritu for the director’s complex and emotionally-wrought drama, “Babel” (2006), a heartbreaking examination of confusion, fear and the depths of love. Set on different continents—Asia, Africa and North America—“Babel” told three separate stories brought together by a single random act of violence when a woman (Cate Blanchett) traveling with her husband (Brad Pitt) through Morocco is seriously wounded by a random bullet fired by two boys (Said Tarchani and Boubker Ait El Caid). Bernal played the drunken nephew of the couple’s housemaid (Adriana Barraza) who tries to smuggle her and the couple’s two children into Mexico. As events loosely connected to the tragedy in Morocco transpire—one involving a neglected Japanese girl (Rinko Kikuchi) looking for love in all the wrong places—fear and confusion manifest themselves into a gut-wrenching failure to communicate.
As “Babel” geared up for a serious run at the Oscars—many critics hailed the film and its strong performances—Bernal went into production on a slew of projects, including “O Pasado” (lensed 2006), a drama about a couple going through a nasty breakup, and “The Bourne Ultimatum” (also lensed 2006), part three in the popular spy thriller series that followed Jason Bourne (Matt Damon) coming out of retirement to defeat his arch rival, The Jackal, once and for all. Bernal then stepped behind the camera for the first time, filming and starring in “Defecit” (lensed 2006), a drama that explored how two distinct social classes interact at a family get-together in Mexico City.