NEW YORK – The obvious question when you’re talking to an actress who has just finished a collaboration with Woody Allen, an actress like “Blue Jasmine” star Cate Blanchett, for instance, is whether that specific collaboration an actor’s dream. After all, so many performers have produced some of their best (in many cases, award-winning) work under the director’s helm. But the answer isn’t necessarily the one you might expect.

“It’s an actor’s dream and an actor’s greatest fear, I think,” Blanchett says. “Obviously when you hear he’s interested in working with you, you take the call, and you’ve already said ‘yes’ before you take the call. There’s such reverence and awe for his work that the danger is you can make your offerings to this sacred altar, but in fact he’s a bit profane as a filmmaker. He’s extremely practical and I really relished it.”

The script, about an Upper East Side New York socialite who loses her privileged lifestyle when her husband is busted for investment scumbaggery, was impeccably structured, Blanchett says. But within that there was a lot of opportunity to nail down the character through specificity and attention to detail.

“She’s on a cocktail of Xanex and alcohol but there’s no discussion with Woody about any of that stuff,” Blanchett says. “It was important to chart all of that — when she was taking what, when she was on what — because obviously films by their nature are shot out of sequence. And she’s a very broken individual with an incredibly romanticized sense of self, so she’s unreliable. You couldn’t always trust what she’s saying about her situation and what is true and what wasn’t.”

And that’s great insight into the tragedy of the story, Blanchett says. Many of Allen’s films get at a sort of truth through a tightrope walk between highs and lows, never bogging down in the dramatic or the comedic alone. “It’s about always trying to keep it buoyant and keeping the absurdity of the situation alive,” Blanchett says. “I think that’s the challenge when you’re in one of Woody’s films. He’s a total shapeshifter, and so you don’t know which way it’s going to land. His films, to me, when they’re at their absolute best, they’re always true. How absurdly deluded some of these characters are. And it’s also the incompatible warmth of some of the various characters that produces the comedy, I think.”

Keeping the absurdity alive wasn’t her responsibility alone, of course, and another tight Allen ensemble helped inform Blanchett’s performance along the way. Filling out the cast this time around are Alec Baldwin (who worked with Allen on his last film, “To Rome with Love”), Sally Hawkins (“Happy-Go-Lucky”), Bobby Cannavale (“The Station Agent”), Peter Sarsgaard (“An Education”), Andrew Dice Clay (HBO’s “Entourage”) and Louis CK (FX’s “Louie”).

“I don’t know how else to do it unless I’m doing it with other people,” Blanchett says. “I’ve been doing theater back-to-back for five years and not making films at all, really. There were a lot of theater animals in the cast, Bobby Cannavale and Sally and Alec and Peter. And then you’ve got the two unique stand-up presences as well. Everyone really threw themselves at the material.”

The actress did plenty of people-watching in New York to help build the character. But she says that even though Allen’s characters are so particularly drawn, there’s a universality to them. “Something I find quite pathetic, in the true sense of the word, is the loss of identity that happens to a lot of women when they attach themselves to a partner,” she says. “They lose a sense of self. That’s something you don’t necessarily observe sitting in a restaurant.”

Indeed, the film called for Blanchett to tiptoe into some truly dark areas as a result of that take on the character. She’s not the sort who has a tough time breaking free of such a thing, however. “I’ve got three boys and they’re a great leveler,” she says. It’s more about winding up into it than out of it. But there were times when the need to dig all of that back up was a challenge.

“The ending we shot a couple of times because he wanted to write something slightly different,” Blanchett recalls. “And so I thought, ‘Oh, phew, we’ve got that out of the way,’ and then you had to go back and revisit it. He wanted to do it in one set-up, so it was quite sort of theatrical in that way. You had to just be on.”

More to the point, though, Blanchett admits that, while she has no trouble compartmentalizing, as an actress, she never truly rids herself of characters and whatever tragic flaws might inform them.

“There’s so much to do and there’s not much time to hold onto it,” she says. “But having played Blanche DuBois [in “A Streetcar Named Desire”] on stage a while back now, that does stay with you. You don’t consciously reference that stuff but the residue sits somewhere. I’m sure the residue of Jasmine is there somewhere, waiting to rear its ugly head.”

“Blue Jasmine” is now playing in theaters.