Michelle Williams appears in two of the buzziest movies at this year’s Sundance Film Festival. In Kenneth Lonergan’s “Manchester by the Sea,” she plays the wife of Casey Affleck’s character, who returns to his Massachusetts hometown to deal with a family tragedy. And in Kelly Reichardt’s “Certain Women,” she portrays a high-powered woman in an ensemble piece based on short stories by Maile Meloy. Williams couldn’t make the trek to Park City this year, because she’s in rehearsals for the Broadway play “Blackbird,” but she spoke to Variety by phone about both her projects.

Let’s start with “Manchester by the Sea.” Can you tell me how you got involved with that?
It was just Kenny. I had done a reading of one of his plays years ago, and had a fondness for him since then. And then I read this and wanted to do it immediately.

What was it about the script that resonated?
There’s no one that can write dialogue like Kenny can. I wanted the pleasure of saying it.

I know you do extensive research for all your parts.
This was definitely no different, even though it’s not a big part by any stretch. But I had the time to give it a lot of time, and I travelled back and forth between home and outside of Boston, where it takes place, and I just sat and waited. I went in coffee shops and shopping malls and watched the local moms pick their kids up from school, and I just sat in the space and waited for things to become clear. I’m sure that I spent more time preparing for it than I spent making it.

What were you trying to absorb from the people you watched?
It’s about specificity and detail. When the title of the movie is “Manchester by the Sea,” it’s very much about a place. That was important to me, the local feeling. I spent a lot of time in those areas, in Gloucester and Manchester By the Sea.

Do you have a Massachusetts accent in the film?
Yeah, I had a lovely dialect coach. And I listened to people who live there – by hanging out, and asking if I could come over for coffee.

And people would invite you over?
I would say, “I want to get things right.” I’m always up for connections, connecting to people.

What about “Certain Women”?
I play somebody very different. Kelly’s films that I have participated in [like “Wendy and Lucy” and “Meek’s Cutoff”] have been very earthy. In this, the first thing I wear is this running outfit. I thought, “Man, I’m an alien in her world right now. I feel so strange.” I play a woman who is trying to have it all: the family, the marriage, the career, the home. She has a deep desire for things to be real and authentic on the outside. And the inside is remaining unchecked.

How did you approach that character?
Well, being a working mother is not unfamiliar territory for me. It was based on really wonderful short stories. I spent some time with those.

You’re rehearsing for “Blackbird” now, after you just completed a run in “Cabaret.” Were you looking to return to Broadway?
I was definitely not looking to do a play at all. But when undeniably great material comes your way, it’s impossible to pass up.

The play deals with sexual abuse. Is it difficult to get in that space?
This is my third day of rehearsals. The damn thing has been advertised for like two months. I’m making my coffee in the morning, and I hear about this Broadway play that I’m doing. I’m having a mini heart attack while I’m pouring my milk. We’re just getting into it.

Do you remember the last time you were at Sundance?
I remember being there for “Blue Valentine,” and being there with my really dear friend Daphne. It’s hard to let these things out in the world for everyone to comment. That’s why it was so important that my girlfriend was there.

You’re been active in making independent film since you were in your early 20s. Do you have a sense of how the business has changed?
I don’t have a take, necessarily. I have a take on raising a kid, and I have a take on things that are present and pressing issues. But I‘m not much of a producer. I’m not much of a planner. I take what comes from the work that’s available to me. I think the change I press for is personal change and personal growth. That’s the thing I’m fighting for. But as far as I can tell, indie films have always felt strapped. You’re always aware that you don’t have enough. You don’t have enough time, you don’t have money, you don’t have enough light. It’s always felt like that.

Many people dubbed last year the year of the woman in Hollywood. Do you feel like the roles for women in movies are finally getting better?
I can’t say that I’ve experienced that. But again, I don’t think I’m quite the right person to ask. I just need just enough work to sustain a life. I can get by on not that much. All it takes for me is just one. This will be all I do this year; it will be this play, because it will take such a large chunk of time. I can get full from one course. Most of my life is very much outside of acting.