In “Silver Linings Playbook,” the outcome is so determined by the characters’ interactions that the story amounts to a veritable chain reaction.

The bi-polar Pat (Bradley Cooper) is convinced the only way he’ll get his life together is by reuniting with his wife, who has issued a restraining order against him. Pat’s dad (Robert De Niro), a chronic gambler, thinks his mojo is spoiled if his son can’t settle down and watch the Eagles game with him. The recently widowed Tiffany (Jennifer Lawrence) gambles with her own feelings for Pat, with whom she’s capable of going toe-to-toe with her own mood swings. And Pat’s mother (Jacki Weaver) prays everyone can just get along.

For the film’s director David. O. Russell, the whole is equal to the sum of its parts.

“Each of the three main characters have their own currency,” he says, “it’s very specific to who they are. To Pat it’s the letter (of reconciliation) and his wife. To Tiffany it’s the dancing and wanting to get closer to Pat. And for Pat Sr. it’s bookmaking and football. These are emotional, life-and-death currencies for each one of these characters. That’s what makes them so specific, and that’s what makes them so emotional, and so funny.”

While codependency runs rampant in “Playbook,” Pat acts as the story’s cog. “We knew Pat would be the foil (through whom) you meet all the other characters and would be your guide through the movie,” says Cooper. “So it was really imperative that we modulate him in such a way that it’s palpable for all the audience, because if it’s too much, the movie’s going to halt and you won’t get on board with him.”

As the puppet master, Russell constantly dances on the edge of all hell breaking loose, and it does, but throughout it all the ripple effect still holds.

“To be universal you need to be as specific as possible,” adds Cooper. “It’s a motley crew of personalities but somehow they are still all invested strongly in each other.”

In Juan Antonio Bayona’s “The Impossible,” it’s tragedy that rallies people together. In the film — a fictionalized account of a family’s ordeal in the face of the 2004 tsunami that devastated many areas of Southeast Asia and claimed the lives of more than 300,000 people — art imitates life.

“We had many of the real survivors around us on set,” says Ewan McGregor, who plays Henry, a man who vacations with his wife, Maria ( Naomi Watts), and their three boys for what they think will be an idyllic retreat in Thailand. “It made you feel an enormous responsibility to present this story with as much reality as possible. People’s worlds were turned upside down and yet even in the shock and horror people reached out and helped each other and strangers connected.”

The family dynamic radically shifts as the young boys, particularly eldest son Lucas (played by Tom Holland), assume adult-level responsibility.

“He was a 10-year-old boy with not a care in the world and all of a sudden he has to look after his mother who is gravely injured,” says Holland. “He becomes not only a pivotal role to her but to others he helps in the hospital.”

This sense of interdependency resonates throughout a number of other films in the awards-season conversation, from the passage of the 13th Amendment in “Lincoln” to tackling the 1980 Iranian hostage crisis in “Argo” to the hunt for Osama Bin Laden in “Zero Dark Thirty.”

What these films have in common are seemingly insurmountable feats achieved through the actions of a determined few.

For Steven Spielberg’s “Lincoln,” the 16th president’s navigation of the tricky corridors of power is aided in no small measure by his wife, Mary Todd Lincoln, whom history has often relegated to the background.

“She is one of the most unexamined and very much maligned women in American history,” says Sally Field, who played the role opposite Daniel Day-Lewis. “But you can’t deny that she was the other side of the coin for him. She was despised by many of the men in his cabinet, but she was the one he could come and tell his nightmares to. She was instrumental in him being and becoming Abraham Lincoln.”

Bryan Cranston’s role as Jack O’Donnell, CIA deputy director of operations in “Argo,” might appear peripheral on the surface, but he’s just as integral to the outcome — the rescue of a small band of American hostages in Tehran — as extraction specialist Tony Mendez, played by the film’s director, Ben Affleck.

“You could say I was phoning in my performance,” says Cranston about his character, who spends much of his time frantically exchanging phone calls with Mendez. “His character is an amalgam of people in the CIA and that was done for a specific reason so as to give it one voice and one face. With ‘Argo’ you look at all the moving parts and how many things could have gone wrong, but it doesn’t.”

With more than 100 speaking parts in “Zero Dark Thirty,” about the hunt for Bin Laden, screenwriter Mark Boal, who won an Academy Award for writing and co-producing “The Hurt Locker,” says the project represented the biggest cast he’s worked with to date.

“So many of the parts were really specific and that made it even more challenging,” Boal says. “The answer was to tell the story through a few key characters and that’s how we did it. Even though this is a procedural it’s also a character study. It’s the glue that holds the story together.”

A young CIA agent based on a real-life figure, Maya, played by Jessica Chastain, acts as the story’s primary conduit. It’s through Maya’s determination, despite opposition from her colleagues and Washington bureaucrats, that the Navy SEALs’ raid culminates in Bin Laden’s compound in Pakistan.

“She represents a very small group of people that stayed doggedly on his trail, even when the world was starting to forget about it,” Boal says. “She is the heart of the film and the heart of a much larger team.”

“Zero Dark Thirty” pulls no punches when it comes to crossing moral boundaries, including torture, in the wake of 9/11. The ramifications not only reverberate within the war’s wider landscape, but among its perpetrators, specifically the character of Dan, a high-ranking member of the CIA played by Jason Clarke.

“When we meet him he is fiercely engaged in the fight for counter terrorism, bristling and puffed with power and strength and bravado,” says Boal. “And in the course of the story his work starts to break him down and by the end he has become a suit and a politician and careful — almost the complete inverse arc of Maya.

“We have lead characters that spur the action but I think what we have really achieved is a rich tapestry ensemble of actors that all had a very specific and very well-defined characters who were all key to the overall development of the events.”

SAG Awards: The Ensemble
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