The Nazi-era Quentin Tarantino film won for best movie ensemble acting.

“Inglourious Basterds,” Quentin Tarantino’s Nazi-era ode to the power of cinematic historical revision, won the Screen Actors Guild’s biggest award Saturday night for movie ensemble acting -- something of a surprise win for the film that featured an international cast of stars, first-timers and unknowns.

In the acting categories, Jeff Bridges and Sandra Bullock walked off with the top trophies for their starring roles in dramas (“Crazy Heart” and “The Blind Side,” respectively). Coupled with their wins in last Sunday’s Golden Globes, both actors would have to be considered early favorites for Oscars, though Meryl Streep is still a strong contender for her role in “Julie & Julia.”

In receiving her award, Bullock frankly acknowledged that her career had been in disarray until it was jump-started by her role in “Crash,” Paul Haggis’ 2004 ensemble drama about fatefully intersecting L.A. lives.

“I dropped out because I wasn’t doing good work,” she said before going on to thank her husband, Jesse James, for being hot and her dialects coach “who stayed in the room when I had a temper tantrum,” among others. In a career filled with popular films, Bullock has found her greatest success with “The Blind Side,” which became an unexpected blockbuster.

For his part, Bridges ad-libbed his way through a genially rambling speech in which he gave kudos to his wife, brothers and musical guru T Bone Burnett, who worked with him on the movie about battered country singer Bad Blake who seeks redemption through love.

“This means so much to be acknowledged like this by my acting family,” Bridges said to the roomful of his peers at the Shrine Auditorium in Los Angeles. “I love being an actor, pretending to be other people.”

In the supporting acting category, the Christoph Waltz juggernaut continued to rumble along. Playing a nasty Nazi in “Basterds” has been very good to the Austrian thespian. He has dominated this award season, winning nearly every honor possible for his role as an almost comically vicious German officer. Backstage, Waltz joked that he was overjoyed “to be an overnight sensation after so many years.”

Six days after winning the Golden Globe in the supporting actor category, Waltz won the SAG equivalent. On stage, he thanked not only Tarantino and his fellow actors, but also projectionists who, he indicated, help bring movie performances to life.

Eli Roth, speaking for the “Basterds” ensemble, praised Tarantino for “plucking actors from around the globe, including the Fangoria convention, and giving them a chance to shine.”

Meanwhile, Mo’Nique continued to dominate the supporting actress category for her performance as a cruel, abusive mother of a teenage girl in “Precious: Based on the Novel ‘Push’ by Sapphire.” Mo’Nique has collected nearly all of the key honors this award season, and the SAG was no exception.

On stage she thanked nearly everyone in the cast, including the baby who was called Mongo in the film. Backstage she said she was proud that the difficult film’s “message got out, and the world heard it and people are now gonna heal.”

At least one movie was conspicuous by its absence. Although James Cameron’s sci-fi blockbuster “Avatar” won the Golden Globe for best dramatic film, and is setting international box office records by the hour, none of its cast were singled out for a SAG nomination.

Kathryn Bigelow’s tense war drama, “The Hurt Locker,” a film critics’ favorite for its taut craftsmanship and central acting triumvirate of Jeremy Renner, Anthony Mackie and Brian Geraghty, also failed to capture any commendations during the SAG show.

The cast of “Mad Men” won for ensemble in a dramatic series just six days after taking home the Golden Globe. Michael C. Hall also repeated, winning male actor in a drama series for “Dexter.” Ditto Julianna Margulies for “The Good Wife”; Fox’s “Glee,” about stage-struck teens at an Ohio high school, for outstanding ensemble in a comedy series; and Alec Baldwin for male actor in a comedy series.

The guild bestowed its highest honor, the Life Achievement Award, on 88-year-old Betty White. She was introduced by Bullock, her co-star from last year’s hit “The Proposal,” who joked that she finds White annoying because she has accomplished so much over her career, including having no less than four TV series named “The Betty White Show.” White retorted about Bullock, “It’s amazing to see how far a girl as plain as she is can go.”

susan.king@latimes.com

reed.johnson@latimes.com