Some of the year’s strongest ensembles were assembled by casting directors with long collaborative histories with particular A-list helmers.

Laray Mayfield met David Fincher on the very day she arrived in L.A., and “after 25 years he’s my dear friend,” through six features that range from “Fight Club” to the forthcoming “The Girl With the Dragon Tattoo.”

Ellen Lewis’ “unbelievably special relationship” with Martin Scorsese began with his segment of “New York Stories” and “GoodFellas” through 12 features, including this year’s “Hugo.”

It’s a classic chicken/egg situation. Did these teams become friends because they’ve worked together so often? Or have they collaborated so often as a result of the friendship?

“Um … you know, I think that … in our case … ah, gosh, it’s really hard to separate that out,” confesses a thoughtful Juliet Taylor with a halting delivery not dissimilar to that of her boss on more than 30 films to date, Woody Allen.

“We spend a huge amount of time talking on the phone, just shooting the breeze about stuff,” she says. “Yes, he’s really a good friend. But I do think that even though we’re gossiping about other stuff, the professional aspect runs really deep.”

For “Midnight in Paris,” she says, “we spent at least a month thinking of different casts and different age groups to make the story work, more than we had on any other picture.” At the same time, she and her team “did a huge amount of research” on the film’s 1920s historical figures, trying to match their actual ages and appearance. “It’s great if it’s exact, but it’s good sometimes to take a step out, so you have a little freedom to play with it.”

Deirdre Bowen says she and David Cronenberg, with whom she has worked on 10 films to date, “have actually grown together based on two things: an appreciation for really strong faces, and a really healthy respect for the script and what story is being told. We then find the right faces to be able to tell that story.”

A face likely to surprise viewers of “A Dangerous Method” is that of Viggo Mortensen as Sigmund Freud, in light of two earlier, violence-oriented turns with the helmer. But, she argues, “Freud is someone who will go out and do battle intellectually, and the character in ‘Eastern Promises’ will go out and do battle physically. There’s a common element there. We knew Freud needed to be a very vigorous performance in order for the script to live.”

It doesn’t hurt a thesp, then, to share the filmmakers’ past. Lisbeth Salander, the eponymous “Girl With the Dragon Tattoo,” was a plum part for which Mayfield says “lots and lots of girls wanted to be considered.” But Rooney Mara was a known quantity to Fincher and Mayfield after “The Social Network.” “We could tell early on that she was going to be a strong contender” to portray “this teeny, tiny little girl who has this tremendous strength inside her.”

This year, U.K-based Fiona Weir racked up her fourth “Harry Potter” film (and fifth credit overall) with David Yates, and a third consecutive credit with Clint Eastwood on “J. Edgar.”

Weir knew “as a filmmaker, David’s taste is quite naturalistic, while the world of Harry is quite heightened. So it was exciting to bring in people like Peter Mullan and Helen McCrory, actors from a very different, natural background, and bring his taste into that world.”

As for Eastwood, she marvels at “his appreciation of what it costs actors in the casting process, let alone being put into the movie.”

“He often prefers to cast with actors who have read with me on tape, because if he’s in the same room with them it’s very clear they’re in the presence of a screen icon, and it makes the pressure even greater.”

(Icons evidently have their own ways of working. For years, Allen wouldn’t even read actors, Taylor says. “He’d meet them for a minute or two. They wouldn’t even sit down. He’d say ‘It’s really nice to meet you, thanks for coming in,’ and it would all be off whatever visceral reaction he had.”)

In the end, what solidifies the director/casting director relationship is a special kind of chemistry renewed with each successful endeavor. “I certainly enjoy the other filmmakers I work with,” says Mayfield, “but because David (Fincher) and I know each other so well and have a shorthand, there’s probably a more natural flow than it would be with people you don’t know as well.”

A marriage of minds and talents, like any marriage, will have its rocky moments. “I know Woody’s taste really well,” Taylor says, “and I almost always agree with it. If I think he’s making a big mistake, he really listens. He definitely won’t go with someone if I don’t think it’s a good idea — but if I think someone is a good idea and he doesn’t, he can be an immovable object, obviously.”

Weir similarly summarizes her work with Yates. “David and I might not start in the same place, but we always end up there.”

When the marriage works, it’s wonderful. “When I met Debi Mazar I felt she was perfect for the role of (wiseguy mistress) Sandy in ‘GoodFellas,’?” Lewis recalls. “Many times the casting process is about creating the vision of the director, and sometimes the director has something so specific in his mind that you’re really playing almost a guessing game with it.

“I remember how exciting it was that someone whom I felt was perfect for this role, he also felt was perfect. And you just pump your fist in the air, and you’re like, ‘That’s so great that this is what you had in mind. Because so did I!'”

SAG Awards: The Ensemble:
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