Coming off Saturday night's win at the Director's Guild Awards, the film earned two film acting trophies at Sunday night's Screen Actors Guild Awards.
It was a crowning achievement for the cast, who won best cast in a motion picture for the British drama.
"We're all dependent on each other's talent," said actress Helena Bonham Carter. "The most important thing when acting is listening, and you'll only listen if you put your trust into somebody else's hands. That's what ensemble is."
The king himself, Colin Firth, was named best actor.
Also a winner Sunday night was Natalie Portman for best actress for her role in "Black Swan."
Co-stars from "The Fighter," Christian Bale and Melissa Leo, won in the supporting categories.
"Any performance is dependent upon everybody else," Bale said. "It's a domino effect. Every single other actor shares this with me. No one's an island on a movie."
Leo is staying calm during this hectic awards season by utilizing an acting trick she developed for auditions.
"I learned quickly to play a mind game with myself, to go into that room, give them my all, walk away and forget about it," she said, "so when I've been going to the awards events, I won't think I'm going to get it. I just don't think about it."
SAG prizes were also handed out in the world of TV.
"Modern Family" was named best comedy ensemble and "Boardwalk Empire" was named best drama ensemble.