'Schitt's Creek' Alum Dustin Milligan on Working With Diane Keaton in 'Mack & Rita' and Being His Authentic Self

Some things get old over time, but being true to who are isn't one of them.

Dustin Milligan and Diane Keaton's new body-swap comedy Mack & Rita is about learning to embrace yourself. The story follows Mack (Elizabeth Lail), a writer who feels like a 70-year-old trapped in a 30-year-old’s body. During her best friend's bachelorette weekend, Mack magically transforms into her 70-year-old self, whom she dubs Aunt Rita (Keaton). With her "inner old gal" (literally) unleashed, Mack no longer feels the need to hide her true self—and even strikes up a romance with her neighbor and dog-sitter Jack (Milligan).

Milligan, who played Ted on the Emmy Award-winning series Schitt's Creek, can admittedly relate to the themes of Mack & Rita. Speaking to Parade.com ahead of the film's release, the Rutherford Falls actor confessed, "Growing up, I never felt like the versions of being a man that media was selling me felt authentic to me. I never felt like even as I became an actor that the version of actor that I was supposed to be—one who is in magazines all the time, or behaving a certain way and living a lifestyle a certain way. That never felt really authentic to me."

"I've been very fortunate where I've had family and friends who have supported me being my authentic self," he said. "But even still, even with that support, it's really, really, really difficult. And even now, I find it hard sometimes to not let those other identities, other ideas of who I'm supposed to be as a man creep in and start to manifest in my life somehow."

One individual whom Milligan admires for remaining "true to who she really is throughout the years" is his iconic co-star: Keaton.

Continue reading to find out what Dustin Milligan told Parade.com about working and kissing Keaton in their new comedy Mack & Rita—in theaters Aug. 12—plus how his character Ted Mullen's puns on Schitt's Creek started.

Your character Jack in Mack & Rita reminded me a lot of Schitt's Creek's Ted Mullens, who is also a very endearing character. Do you like playing these lovable characters?

There's something for me that I try to always play earnestness. I think that can manifest in a lot of different ways, and even like the few times I've been able to play like villains or like really awful people, there's always an earnestness that I think I like to tap into because then there's an appeal. There's kind of a human connection no matter what. I never really go into something trying to be lovable or trying to be any kind of end result for the audience. I just go into it being like, "What's the version of this in which I'm playing an authentic human?" and hope for the best.

Related: 20 of Diane Keaton's Best Roles

Like Mack, was there ever a point in your life where you felt like you had to repress a part of yourself or where you felt like an outsider?

Yeah. This movie, the theme of being who you really are, recognizing who you really are on the inside, and shedding all of these assumed, taken-on identities that the world is constantly thrusting upon you—and especially with social media that we're being sold—you know, "This is how you should be happy. This is how you should be sad. This is how you should go on vacation. This is how you should enjoy food." All these things that we're told what to do, and there are these expectations—that's something that my entire life I've felt.

So yes, the themes of this movie definitely are something that I identify with and that I also think with Mack, specifically, her going through that journey in front of the audience, I think it's gonna be something that's gonna resonate really strongly.

The Jack character, he's almost a little bit further along in that journey, but we don't realize that quite until later in the movie. He's got a line where he's like, "I know I'm not what you expect of someone like me. I know that, but I'm okay with it." And it's something that I think between the two characters is really admirable. I hope that that's the main takeaway, along with all the laughter and the fun and the love.

To me, the message behind the film was being comfortable in your own skin.

Yeah, which is very difficult to do, to be comfortable in your own skin. It's not an easy task.

You've shared the screen with icons like Catherine O'Hara and now Diane Keaton. What was it like working with Diane on Mack & Rita?

It was such a joy because honestly, you never know what you're gonna expect when you work with somebody of her status—her iconic status. I was understandably a little nervous and you're not quite sure what the first day is gonna be like. But our first scene together, we were in a fine dining restaurant known as California Pizza Kitchen. I sat down first, and we're about to start rehearsing the scene, and she walks in fully what you would expect Diane Keaton to look like: wearing this white long flowy pantsuit and this huge wide-brim hat with the straight hair and the glasses and everything. Like, it was just so picture perfect with what you expect her to be, and then when she sat down and we started actually talking, she immediately wanted to kind of break through any walls and any preconceived notions that I would have had and just start joking with me and like making fun of me a little bit and letting me make fun of her

It was just this really fun and disarming thing that happened almost immediately where she was just like, '"his is how I want to do this! Llet's play, let's have fun." And it was just such a joy. Right away you get energized and charged up. Not to mention the wafting scents of all the pizza around us. It was just a memorable first day.

Are you a longtime fan of Diane's?

Yeah. I feel like it's one of those things where she's been such an iconic figure in cinema, right? Because coming up through, especially the '70s—that era was just so formative. I'm an '80s baby, so it's like so formative in terms of the movies that you're watching as a young kid when those images, those first movies that your parents are watching or whatever are being sort of imprinted into your brain. So yeah, huge, huge fan.

And then also just a fan of how she's lived her life since then and continued to be so authentic and so true to who she really is throughout the years and continued to work. That's not an easy thing to do either, but she's managed to pull it off.

Was it nerve-racking going in for that kiss, knowing you're going to kiss this iconic actress?

You know, I get that question a lot. It is one of those things where I think people from the outside have an expectation of what that must be like, but the reality is that you have an entire crew of people around you watching. It's very technical. You really just want to make sure that everyone's comfortable with what's going on. The fact that you go through rehearsals and you're like this close to each other without actually kissing, you know what I mean? It kind of dissipates the nerves a little bit. And also on top of that, she was just so lovely and great and sharing all of her Altoids with me! It was much less nerve-racking than I think it could have been.

Did she say anything after you guys kissed?

Probably just like "Thank god that's over," which is weird, because that's actually the same thing everybody says after they kiss me.

Well now you've joined that long list of Diane Keaton's onscreen love interests. Keanu Reeves, Jack Nicholson... You're in good company.

Yeah, I guess so! I never thought of that.

In the movie, Mack feels like she's a 70-year-old inside. Do you feel young at heart, or do you feel like you're an old soul?

I definitely feel like I lean more towards youthful energy most days. I always try to in general with how I go about my days, and if there's any big decisions to make or anything like that, I always keep in mind this thing that I came up with when I was 11 or 12—and that is to always think about what the six-year-old version of myself would think about whatever it is I'm doing, however I'm spending my time, how I'm living my life, and then think about the 60-year-old version of myself. To just kind of keep in mind that there are these two versions of yourself that will exist, hopefully, and that have existed and that you are that future version of yourself already and you are still that past version of yourself and all of those, all three of you—the person that you are now, the person you will be, the person you have been—all three of them are sort of alive within you at any given time, and you should honor still what that child wanted you to be. What they imagined you would be. The kind of good person that they thought you would be. The pure person they thought you'd be.

And then the 60-year-old version of yourself who's kind of like, "Eh, you can't be perfect, you know. You did your best." You want to honor both of those versions of yourself at all times. So, a mixture of old and young souls, I guess.

Related: Annie Murphy Reveals Her Favorite Alexis Rose Story, Plus Her Idea for a Schitt's Creek Spinoff!

Of course we have to ask you a Schitt's Creek question. Your character Ted was known for his clever puns. Do you have a favorite pun of Ted's?

There were a lot of puns that Ted made. This actually wasn't in an episode, because the puns started when we were doing these little kind of extra bit videos—like extra visits with the characters in either the motel or whatever—and mine was in the vet. My first little extra video that I did, I was referencing just things around the office, taking a tour around the office and I just started making all these puns about all the animals there. In making the crew laugh in doing it that was the moment that that aspect of Ted was born. So that's my favorite, because it was the first time it happened and it ended up becoming such a classic part of this character—that he just makes the worst and dumbest jokes all the time, which is similar to me in real life.

Mack & Rita opens in theaters Aug. 12

This interview has been edited and condensed for clarity.

Next, check out 30 facts you never knew about Schitt's Creek.