The small irony of Ordinary Love is that the titular affection -- the easy, lived-in love between a long-married couple -- is brought to life onscreen by two extraordinary actors: Lesley Manville and Liam Neeson, who come to the project with his and hers Oscar nominations (she for Phantom Thread; he for Schindler's List).

In director Lisa Barros D'Sa and Glenn Leyburn's drama, out now, Joan and Tom's vows of in sickness and in health are tested when she is diagnosed with breast cancer, and they must adapt to a grim new normal. Through tests and surgeries, chemotherapy and its side effects, Manville and Neeson deliver sensitive, understated performances, painting a portrait of a deep, enduring -- if ordinary -- love. In real life, the actors now share their own relaxed repartee.

"It's very nice to see Liam, because I haven't seen him since we made the film," Manville said, seated next to Neeson. "Although he sends me funny messages all the time, with these little cartoony things that he finds online somewhere."

"I love WhatsApp," he chimed in in his trademark Irish brogue.

"He loves a WhatsApp message in the middle of the night," she giggled. In discussion with ET, Manville and Neeson opened up about their crash course in getting to know one another and why Neeson won't do another superhero movie.

ET: This is your first time working together, but had you known each other before this?

Liam Neeson: No.

Lesley Manville: Nope! Completely new to each other. Everybody involved in the film on the producing and directing and distributing side breathed a big sigh of relief when we did meet and just hit it off.

I assume you knew each other's work. Do you each have a favorite project the other has done? Or a project that left an impact and means a lot to you?

Manville: Obviously, I've seen lots of Liam's work -- not on stage though, sadly. But I've seen most of his stuff, from the early days up until now. And for me, Schindler's List was a real highlight -- but that's not to negate all the amazing stuff he's done since then. There was always an enormous amount of honesty in what he did and truth, and that's all you can hope for in an actor.

Neeson: Yes, there are a couple of Mike Leigh films, and she was like -- and I mean this as an absolute compliment -- like someone who had literally walked in off the street and was acting, but you didn't see any acting. It was so real. That's what she's like. I had the pleasure of seeing her on stage in Eugene O'Neill's masterpiece, Long Day's Journey Into Night, and after that performance, she came and met me up at a restaurant very close to where I live. And I remember thinking, "Is she tired? Are you tired?" She had given this huge performance! And she says, "Oh, no. I'm totally fine." So I thought, "OK, this lady is the real deal." And she's just lovely. She's very easy to get on with, and she's just--

Manville: Crucially, he also wanted somebody who was quite a lot shorter than him. It just makes him feel good, so I was a big pick in that area.

Neeson: So I didn't wear lifts anymore. [Laughs]

Was that the first time you met, then? After Lesley's performance?

Manville: That was it, really! We knew we were going to do the film, and I was in New York doing the play, Liam lives here, and he walked into my dressing room after Long Day's Journey Into Night and then we went off and had dinner together. A few days later, our directors came over and we had a few afternoons together, just chewing the fat on the film. It was very easy and very good-humored. We were all getting on. That was it. That was the first time we met.

There is a deep intimacy between these characters. Was that all you needed to jumpstart that connection -- a few hours to chew the fat -- or did developing that shared intimacy require any additional work?

Neeson: At the end of the day, it boils down to the script. And the words were there. Owen McCafferty had written it. After 63, 64 movies I've done, it was certainly one of the best scripts I've ever read. And I remember thinking, "You do not have to act this. Just breathe it. Just accept it and say what Owen has written." I think Lesley felt the same too, even though she has to go through the cancer process, of course. There was tough research to do there, but--

Manville: And neither of us brought any fuss or ego to the set. We just got there and got on with it.

On a movie that is as emotionally demanding as this is, how do you want to be supported as an actor and how did you want to go about supporting the other one?

Manville: I don't know, really. It's not calculated. We're both decent people. So, I'm respectful of anybody and respectful of the hard day, the long physical day that the camera team have had and what everybody put into it. Certainly, for my part, the makeup/prosthetics team were really putting in some hours to get that bald cap on me for many days. I don't think there was a lot of nursing that had to go on.

Neeson: And the crew were very sensitive too, to the subject matter. I'm not saying that they tread on eggshells all the time -- not in the least -- but communally, they were very sensitive to what we were doing.

Courtesy of Bleecker Street

Now that you've worked together, was there something that surprised you about seeing the way the other worked?

Manville: No, actually. I wasn't surprised. From the minute I met Liam, I thought that it was going to be easy in all the right ways, that I was going to be able to play this character. I definitely had to leave my ego at home -- in terms of where I had to go and how Joan looks in the film, it was quite brutal -- but I knew I was in safe hands, really. Everything felt all right.

Liam, was there anything that surprised you about seeing Lesley at work?

Neeson: Sometimes at night, I would question what acting actually is. You know, there's so many books written about it and there's so many types of acting -- the method school, this school, that school -- and stuff. But James Cagney, when he was asked by someone how to play the scene, he famously said, "You walk in the room, plant your feet, speak the truth." And I thought, "Today, this actress just spoke the truth to me. And hopefully, I responded to her with the truth." If that makes any sense. It was to try not to act.

Liam, you go back and forth between more intimate, character-driven dramas like this and these action movies you've really sort of revolutionized. Is what you take away from the experience of making those very different types of movies the same? Or do they each give you something different?

Neeson: Well, the action movies -- and I'm doing one at the moment up in Winnipeg -- you know, I'm repeating myself: I'm just trying to make them real, even though they're absolutely crazy Tom and Jerry-esque type situations. But I try. If it's dumb dialogue, I just try and say it and try and make it seem real, you know? Sometimes it works, other times, it doesn't, but...

You also did The Dark Knight Rises, which was part of a trilogy that shaped the modern era of superhero movies we're in today. Is that a sandbox you'd like to return to, the superhero-verse?

Neeson: I'll be honest with you, no. It's not. I'm really not a huge fan of the genre. I think it's Hollywood with all the bells and whistles and the technical achievements and stuff -- which I admire -- but I have no desire to go into the gym for three hours every day to pump myself up to squeeze into a Velcro suit with a cape.

Manville: Aww, but I would pay to see that!

Neeson: Oh, stop it. [Laughs] I admire the actors and I know some of the actors who do it -- and do it fantastically. It's just not my genre, it really isn't. The first Star Wars, I was in that, that was 22 years ago, and I enjoyed that, because it was novel and that was new. I was acting to tennis balls, which were ultimately going to be little fuzzy furry creatures and stuff. That was interesting, acting-wise, to try and make that seem real, but that was the last. It's quite exhausting.

Meanwhile, I would pay to see you, Lesley, do one of these Liam Neeson action movies. I want to see you have a particular set of skills and somebody's going to pay.

Manville: Listen, don't be under any illusions. I could kick some a** for sure!

Neeson: Yeah, I do believe it.

Ordinary Love is now in theaters.

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