Mary Elizabeth Mastrantonio's Broadway turn in 'The Winslow Boy'

Close your eyes and listen to Mary Elizabeth Mastrantonio onstage, and you'd swear she's starring in a new modern drama.

In Terrence Rattigan's "The Winslow Boy" -- a Roundabout Theatre Company production that opened Thursday at the American Airlines Theatre -- she plays Grace Winslow, whose young son is enmeshed in a court case and tabloid scandal. Her husband (Tony Award-winner Roger Rees) is determined to clear the boy's name. A sister is stringing along a fiance she may or may not love. The only thing missing is the family's reality show.

Then, you open your eyes, see the period costumes and remember the play is set in London 100 years ago.

Her Broadway resume ("Man of La Mancha," "Amadeus") is as varied as her work on film ("The Color of Money," "The Perfect Storm") and TV ("Grimm," "Hostages").

She is married to Irish director Pat O'Connor, and they have two sons. Mastrantonio, 54, chatted with Newsday in her dressing room before a performance.

I'd just moved back to New York two years ago -- I'd lived in London for 20 or so years, so I know English culture. It's funny, there's no way in hell they'd ask me to play Grace in London. It's really refreshing to be English now that I'm back in America.

Oh, yeah, we had wonderful friends with whom I raised my children. That's a long time to spend with people. They are your unwritten journal. They've witnessed ... you know ... when we all sheepishly come out of our houses hoping no one heard us screaming at the children that morning.

It was time. Both my children were transitional, one going into university, one into high school. You either do it then or....

I've no idea. It's really comical -- I was recently thinking, "Could it be ... me? Maybe I'm the evil source orchestrating this whole conspiracy." What I do know is that it feels a bit like starting over.

Well, they don't need a lot of women my age. So....

Oh, I think it's worse now, because of all the things people do to their faces. It's fictional. It makes up how you look. I don't know about you, but nobody I know looks like that in real life.

No. Television's funny, because you don't know who the character is ... at all ... when you start.

Right. So ... I assume she's intelligent, ambitious. And has straight hair.

Evidently, first ladies don't have curly hair.

No. Sometimes -- I have to be honest -- I look at it and think ... it's bloody long. It's like an alphabet from a language I don't know.

That's so sweet, because as an actor you're thinking, "Should I be crying here ... or...?" I only worked on that film for nine days. I was never in the tank, I never got wet, like the guys. But I tell you, that director, Wolfgang Petersen, runs one helluva set. And he knows how to talk to actors. I bristled at some line I didn't want to say, and he just looked at me and said, "Now, don't be nasty," and I thought, "Ohhh, he knows I'm feeling vulnerable, and when I'm vulnerable, I swipe like a cat."

Roger Rees, yeah.

Oh, no. I don't draw anything. Except conclusions, sometimes. We were in an important notes session, and Roger was passing this around.

I said, "You're gonna get me in trouble with the teacher."

Yeah. Once again ... straight hair.