Naomi Watts's career is a testament to her ability to defy type-casting. One would hardly expect the same actress to have played Princess Di, a pregnant, Russian prostitute, and a bright-eyed ingénue turned bitterly disappointed thespian—as Watts did in Diana (2013), St. Vincent (2014) and Mulholland Drive (2001), respectively. And the British-born, Australian-raised 48-year-old shows no signs of settling in that department. Fresh off the heels of her turn in Showtime’s Twin Peaks reboot, Watts stars as Susan Carpenter, a single mother to a phenomenally gifted older boy Henry (Jaeden Lieberher) and charmingly mischievous younger one (Jacob Tremblay) in The Book of Henry, in theaters June 16. Much like Watts, the film, directed by Colin Trevorrow (director of the upcoming Star Wars: Episode IX), upends traditional categories: a quirky family drama at the start, it quickly nosedives, after a momentous incident, into darker thriller terrain, with Watts leading the charge.

Watts descends fully into that dark tone in the forthcoming Netflix series Gypsy, dropping June 30, in which she stars as a therapist who becomes questionably involved with her patients, to ill effect. And later this summer, she will appear as Rose Mary Walls, the controversially kooky mother in the film adaptation of Jeannette Walls's best-selling memoir The Glass Castle.

Jaeden Lieberher, Jacob Tremblay, and Naomi Watts in The Book of Henry.

Alison Cohen Rosa / Focus Features

The film is very enigmatic. At the outset, Susan relies heavily on her son Henry—he manages the family’s finances, for one—while she takes on a more child-like place in the family. And then things change. How would you describe Susan’s trajectory over the course of the movie?

She’s at a point where things seem to be working well as they are and she hasn’t questioned it because it works. And obviously, it’s not a conventional way of parenting, at all, but [Henry has] showed that he has these abilities. She’s kind of a kid in many ways herself, playing video games—it’s like a role reversal. And he just knows how to take care of that side of business. She allows it to happen because she’s just trying to make ends meet and do her job. And then things happen, those things that we can’t talk about, and you see her having to get on a fast track of growing up, basically. And I really loved the material the first time I read it because there is so much heart in this story, and yes, the fact that it did almost turn around and reshape itself into another genre. There’s a bit of everything in this movie for everyone.

You had worked with both of the young actors before [Jacob Tremblay in Shut In and Jaeden Lieberher in St. Vincent].

It was great because you go into these movies very quickly these days—there’s not a lot of prep time—and so to make relationships appear like they’re authentic and have all that chemistry and history, it’s tough to do quickly. And when you know them and you’ve already done one round, it’s easier.

Did the story resonate with you on a personal level because you’re a mother with two young sons?

Yes. I mean, your job as a parent is to protect your kids; their health and safety and obviously imparting good values, as well. And the idea of having one of your children in trouble, that’s just the biggest fear one can go through, and biggest source of pain. So yeah, I can relate to it on that level.

Naomi Watts in The Book of Henry.

Alison Cohen Rosa / Focus Features

One of the main storylines is the suspected abuse of the next-door neighbor Christina (Maddie Ziegler) by her stepfather, and how to save her. There is a decision to be made between a more violent solution, one Henry dreams up, and then taking a more adult, rational tack. At one point your character even says to herself, “It’s time to start being an adult.”

Yes, finally she has that epiphany. And it’s such a horrific thing that’s going on, and she’s trying to get the help they need and they’re not being responsive and reaching out, so they decide to take matters into their own hands. And Henry has all this wisdom and has always been the one who’s run the show, so she’s just always trusted him. And the injustice of it all is the biggest thing that’s weighing her down, again, as a protective mother and that sort of just drives her into a sense of this is an absolute necessity, she’s gotta do it. But then not necessarily in that way, and finally she has a moment.

It felt to me like a parable of how do we deal with really horrible things in our lives. Given the world today, it resonated even more strongly for me and I wonder if it has for you now, as you’ve watched it, the idea of how we choose to react to things?

Yes, a lot of people have talked about that. When you’re in chaos and it’s all around you, and you can’t rely on the powers that be, it’s very scary, it’s very scary. How do you exist? How do you protect yourself? You feel like you have to take matters into your own hands. And this is one of those moments.

Naomi Watts in Netflix's Gypsy.

Alison Cohen Rosa/Netflix

Right. But reason does prevail, a nice antidote to the ways things are going these days. You have the Netflix series Gypsy coming up. How much can you divulge about that?

There aren’t so many spoilers there. It’s a Netflix show and I play a cognitive behavioral therapist (CBT), and she’s getting inappropriately involved with some of her patients and her patients’ others. So it’s an interesting character. She’s very flawed. And her curiosity gets the better of her and she finds herself in a deep, dark web of lies.

Was that fun? Or stressful?

Both. It’s fun and stressful. But definitely an interesting character to play.

Did you do any research to prepare for her professional background?

I wanted to learn about CBT therapy definitely and I met with two therapists, one who was just a regular one I went out to and said, "Can I meet?" And I just went in and talked about my own life. And the other one is actually the sister of the show creator [Lisa Rubin], and she kind of acted as a consultant. It’s all about controlling thought patterns that could create destructive behavior. So that was interesting to learn about.

Was that something that seemed appealing to you to delve into?

I think what was appealing to me was that it’s an exploration of her identity and I find that an endlessly fascinating subject in terms of the characters I want to play and the things that resonate with me. I can relate to that. I’ve definitely had moments in my life when I’ve wished I was someone else. I think we all do. And in that regard it’s sort of a cautionary tale. You get to sit at home with your life in the comfort of your home, in the safety of your relationships, and you can play that fantasy out whilst watching this woman live it out for you.

It's the first time you've done something like a Netflix show. Was that different for you, because your character is living in someone’s home versus being on a big screen? Is that something you’ve become accustomed to, the idea that film and your projects are going to be digested that way?

It’s a sad situation that people don’t leave the house much anymore. And seeing films in cinemas has become… it doesn’t happen as much. It’s very hard to keep a film in theaters these days for a very long time. Yeah, with TV, there’s great writers there, there’s great characters, great female-driven shows so…

Naomi Watts with Kyle MacLachlan in Showtime's Twin Peaks.

Suzanne Tenner/SHOWTIME

You go where the good parts are.

Exactly.

And you have the film adaptation of The Glass Castle coming up. Had you read the book prior to signing on to the film?

No, I hadn’t. I obviously did read it as soon as I knew about it, but I had never actually read it.

What was your reaction to it and to Rose Mary Walls, whom you play?

Yes, I play Jeannette Walls’s mother. I thought she was a fantastic character. I spoke to her on the phone. And saw a lot of the footage that was available and all the interviews that Jeanette did, apart from reading the books, hearing her speak about it. And we emailed back and forth and spoke on the phone several times. And I just thought [Rose Mary] was a fantastic, larger-than-life character, and it tapped into my sensibility and my world because I sort of grew up with artistic people in my life who were busy just creating all the time. And that was a necessary thing for them to do and sometimes that meant the kids were roaming free a little bit. So I definitely related to that world that Jeanette talks about.

The memoir is from Jeannette’s point of view and then you have access to Rose Mary’s insight, so with all of that, how did you go about crafting her as a character?

Well, the video footage mostly and the voice, which was quite extreme. She’s got quite a strong... obviously I’m not American so there’s that part and she’s quite, not Southern, not a Southern drawl, but you really had to listen to every bit of tape that was available and I recorded our conversations. And then the story is over quite a large passage of time so we really went for it with her look and went through the aging process.

Was that fun?

It’s always fun. You want to make the character be as truthful as possible and we gave it our best. I just loved her spirit. I think they were obviously struggling all the time and she managed to pep everyone up all the time. She wasn’t going to let the hard times crush them.

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