That time a diva cow dared to upstage Meryl Streep

That time a diva cow dared to upstage Meryl Streep, What happens when an A-list cast and an Oscar-nominated filmmaker go Into the Woods? A whole host of stories come back with them.

Director Rob Marshall created a company out of Hollywood's finest to sing, act and dance — and, in some cases, fly — their way through Stephen Sondheim and James Lapine's fairy-tale musical mashup (in theaters Christmas Day).

The castmates recalls their time in the Woods with tricky bathroom breaks, a secret pregnancy and one annoying cow.

Suddenly Sondheim. Without the award-winning success of Marshall's Chicago, there could be no such big-screen undertaking of Into the Woods, says James Corden, who plays the Baker.

The actors' familiarity with performing Sondheim, though, ranged from Emily Blunt never having been in a musical to Christine Baranski's longtime work with the composer's material, from a full production of Sweeney Todd to workshops of Sunday In the Park With George and Assassins.

"You're always keeping up with his brilliance and his intellect and his insight," says Baranski, cast as Cinderella's stepmother.What sets Sondheim's show tunes apart is the fact that "you have to study them, you have to know them, because you make assumptions and he always trips up your assumptions," says Meryl Streep, whose performance as the Witch is up for a Golden Globe next month. "The rhythm isn't quite what you thought — it's intricate, but everything is driven by the thought behind the song."

The reasoning: Sondheim wants the singer to pay attention and be kept on their toes, says Blunt, another Golden Globe nominee as the Baker's Wife. The music "kind of arrests you and it forces you to follow the characters because it never goes where you expect."

When nature calls. The movie filmed outside in actual forests in the English countryside but Marshall also created a musty, misty environment on two soundstages ("Almost airline hangars," Streep recalls) at Shepperton Studios near London.

Even on the built sets, "we had actual birds living in the trees," Blunt says. "We had moss, we had trees that they added onto to make them magical. Who likes working with green screen when you have that?"

The root systems and electrical wiring made walking treacherous, "particularly in our high heels," says Baranski. But authenticity was lost because, unlike a real forest, you could always locate what direction you were headed.

"I kept looking for the light to know where the bathroom was," Streep says. Adds Tracey Ullman, who plays Jack's mother: "I caught a couple of the crew peeing on the trees by the end."

And no wonder. The bathrooms "were these tiny cubicles," Baranski says. "I'm in my costume and I was like, 'I need some help here! I can't find my pantyhose!' "A treat for the Baker's Wife. Her character makes bread onscreen, but in reality, Blunt had a bun in her own oven: She was 3½ months pregnant when rehearsals started in 2013 and 7½ months when filming ended. (Daughter Hazel, Blunt's first with husband John Krasinski, was born Feb. 16.)

It was trippy for her to be playing a woman who can't have children because of a curse. And to disguise her growing stomach on set, "I hid behind every tree by the end of it and every character I could find," Blunt says. "James Corden was a fantastic mask for me."

Young British actor Daniel Huttlestone (as Jack), who would blow kisses at his female co-stars, was the last to find out and he was "appalled," Blunt says.

"Daniel went, 'I want to end up with Emily' and (co-star Billy Magnussen) said, 'Dude, you can't because she's pregnant.' He said, 'No, you're not,' and I went, 'Yes, I am,' and I pulled my dress back. And he went, 'No! When?!' "

Still, the 15-year-old was one of Blunt's favorites. "I was a bit in love with him. I was like, 'What's wrong with me? This is sort of sick.' "

Meryl Streep, stuntwoman supreme. While her Witch tended toward the magical, there wasn't a whole lot of special-effects wizardry involved for Streep.

The character is introduced when she blows down the Baker's door, and "it came off every time with an explosion," Streep says. "It was a little bit terrifying to stand behind it."

Another scene involved hanging upside down. "I was worried about that, too," Streep says. "That was hard."

Admittedly, none of it was as treacherous as some of the other stunt work Streep has done in her career — the whitewater-rafting scenes of 1994's The River Wild come immediately to her mind — yet flying down from a tree can still be fear-inducing, even with a stuntman's help.

"He said, 'I've got your calves,' and I said, 'I know, but they're slippery!' " Streep says with a laugh.

The only CGI in her performance came during the Witch's physical transformation, "because, well, it had to be done," Streep says.

"That's one thing Meryl Streep can't do, guys," Blunt adds. "Sorry."The bold and the bovine. Corden respected Marshall's decision to go with less green screen and more practical effects, but he wished the director would have gone with an animatronic cow instead of a real one that was a "(expletive) nightmare," he says. "Five minutes was too long with that cow."

Played by an animal named Tug, Jack's cow Milky White is integral to the Baker and his wife's journey toward having a family, since it's one of the items that the Witch seeks to break a longstanding spell.

"Don't get me started on the cow," says Ullman, who has some screen time with it — though not as much as Corden.

"You just don't know what it's like when you're doing a scene, and Meryl Streep is giving a phenomenal performance in only the way that she can and it's scuppered by just 'Moooooooo,' " says Corden.

"That cow was the biggest diva on this set. She would stomp off to her trailer, she'd only have a certain type of straw in the morning. It didn't change my mind about eating burgers working with that cow."