As summer winds down, director Megan Park stokes the fires of nostalgia with her second film, My Old Ass. It’s a coming-of-age story set in the sweet final weeks before her 18-year-old protagonist leaves her lakeside hometown for college in the big city. Maisy Stella (“Nashville,” “Flowervale Street”) plays Elliott, a free-spirited teenager who, on her birthday mushroom trip, comes face to face with her “old” 39-year-old self (Aubrey Plaza), who gives her some good advice and warnings that change her relationships with her family and friends.

“This change and the passage of time are so sad, but also beautiful,” says Park diversitywhen you think back to that transition period between childhood and adulthood when you know your life is about to change but you can’t say exactly how.

“Sweet” is a word Park uses liberally (and lovingly) when talking about her work. In fact, the writer-director is on a mission to make emotional and “sweet” films, although some people in the industry, which tends to prioritize provocation, don’t find that particularly “cool.”

“There have been so many cult films like ‘Stepmother’, ‘Now and Then’ and ‘My Girl’ that are so emotional, heartfelt and sweet, but also had these low points that shaped and moved me. It would be an honor to make a film that is seen as such a film. I think those films are very cool,” she says, adding a pinch of cheekiness to her voice for emphasis.

Although Elliott is a young woman coming of age in Canada, Park (who grew up in the small town of Lindsay, Ontario) insists the story is not autobiographical. “I identify with every character in this film in very different ways,” she says. “I’m part of Elliott, I’m part of the mother, I’m always there. The film gave me new meaning over the course of filming because my own life was changing: I had another child. I recently lost my father.”

“It’s so exciting and a great honor to see how people from all over the world, from different backgrounds and ages, are responding to the film. I had hoped this film would speak to everyone with a heart, but it’s really exciting to see that it’s reaching the old people too,” she continues.

When Park began work on “My Old Ass,” she was “in her feelings,” as the teens say. She had just finished filming her first feature, “The Fallout” (2021) – a drama about the emotional aftermath of a school massacre starring Jenna Ortega and Maddie Ziegler – and was spending time in her hometown.

“I was sleeping in my childhood bedroom and I was thinking about the last time I made up dances with my school friends,” she recalls. “I just thought, ‘Wow, imagine if I had known that was the last time. Would that have ruined everything?’ I didn’t know, but I was just very nostalgic and had all the mixed feelings you have when you come home.”

In her twenties, Park wasn’t a particularly nostalgic person. “I was much more blissful and kind of selfishly lost in my own thoughts,” she says. But she has become much more so as she’s gotten older.

“The more of the world you see and the more crap you go through, the more you appreciate that bubble of childhood and the gift of my parents of having this blissful calm where I don’t see most of the crap in the world,” explains Park, 38. “Then you want to try to recreate that as best as you can for your own children and protect them. Becoming a parent has made me a lot more sentimental. How could it be otherwise?”

When we meet on the rooftop of her West Hollywood hotel in early August, Park is in town to attend a special screening of My Old Ass—only the second time she’s seen the film with an audience, following its buzzy Sundance debut in January. Ahead of the film’s Sept. 13 release, Amazon MGM Studios has embraced the late-summer spirit by hosting cozy campfire-side advance screenings in New York and Los Angeles, including a sold-out outdoor Cinespia screening.

“We talked to a lot of people who loved the film and saw it at Sundance, but the team there immediately understood what the film was about, it was just so clear,” Park says of working with the studio. “We were confident that they would be able to get the film in front of the right audience in a way that was true to the film. They’re taking the campfire summer feel of the film and marketing it in a way that’s really unique, exciting and different – and I hope the film is too.”

This is all new for Park, who had already built a successful career as an actor (“The Secret Life of the American Teenager,” “Charlie Bartlett,” Hallmark’s “A Christmas Wish”) before moving into directing. But “The Fallout” was shot and premiered amid the COVID-19 pandemic, so everything was virtual, including winning the Audience Award at SXSW.

“The whole film was full of joy from start to finish,” Park says of filming “My Old Ass” on the shores of Lake Muskoka in Canada (where she spent summers as a child) and the performance she now presents to audiences. “I don’t know if it was because we were all up there together and it really felt like summer camp and we felt connected in that way. Everyone involved felt so close and like family.”

Park’s film family also includes the team at LuckyChap – the company behind Greta Gerwig’s billion-dollar hit “Barbie” and Emerald Fennell’s sizzling drama “Saltburn,” which was co-founded by Margot Robbie. Earlier this year, Robbie admitted that the company has a “penchant for actresses who become writers and directors”: Fennell, Gerwig, Olivia Wilde and now Park.

“When I hear you say what a friendly atmosphere I have working with you, I am speechless,” she says when I mention Robbie’s quote.

“The Fallout” not only earned her a place on diversity 10 directors to watch in 2022, but it also caught the attention of Bronte Payne, LuckyChap’s vice president of film, who reached out to set up a Zoom meeting. They hit it off immediately, so Park brought up an idea she’d been considering.

“I had this one-line logline in my head: ‘This girl who takes mushrooms and trips and meets her older self,’ and they were like, ‘Honestly, we love that,'” Park recalls.

From there, things moved very quickly: Payne introduced them to LuckyChap co-founder Tom Ackerley, then Robbie and Josey McNamara, and less than a year later they were on set. The high-profile indie film (also produced by Indian Paintbrush’s Steven Rales, with LuckyChap’s Payne serving as executive producer) had its world premiere to a sold-out crowd at the Eccles Theatre.

“I was so scared. I thought to myself, ‘I don’t know if I can make it through this,'” Park recalls. “But after the first laugh – when the boat crashes at the beginning – a part of me relaxed. It was incredible that there was such a wonderful reaction to it, but it’s scary every time.”

When she sat down to write the script, she wasn’t thinking about the audience; she was simply processing her own feelings about life’s ups and downs. So the way the script resonated with viewers of all backgrounds and ages was a welcome surprise. “People have had such strong, visceral emotional reactions that I didn’t expect,” she says. “The dream is to make people feel something – which is hard to do today when people are jaded and there’s so much content.”

The test screenings proved particularly fascinating in terms of the generation gap. “What the people in their twenties – the ‘younger asses’ – took away was so different, but still the same, but they just felt different than the ‘older asses,'” Park says. Younger audiences recognized the nostalgia, but felt mostly represented by the film’s Gen Z cast. “It was so fun, like hanging out with my friends,” and “I learned a lesson from it about time and how quickly it passes,” they said, according to Park. For older viewers, “there was definitely more of a kind of sadness, like, ‘Oh, damn, yeah, I’ve been through that,’ ‘I’ve experienced that loss,’ or ‘I regret that,'” she says. “In your twenties, you often don’t have any regrets.”

Parks’ relationship to the material has also changed over time. It’s been two years since she wrote the film, and even in the seven months since Sundance – and since Amazon MGM Studios snapped up the comedy in a lucrative $15 million deal – so much has changed in her life. She recently celebrated her 38th birthday and is now a mother of two (she and husband Tyler Hilton welcomed their second child, son Benny, in July; their daughter Winnie is four), and in June her father Richard died after a sudden illness.

“I didn’t understand grief the way I’m beginning to understand it now,” she says seriously. “I feel like everything I’m experiencing right now is 50% joy and 50% sadness at the same time, and you learn that the older you get. And sometimes, unfortunately, even when you’re young.”

Park’s parents (her mother Debbie gets special thanks for “My Old Ass”) were never particularly involved in the Hollywood scene. “Their measure of success was, ‘Are you happy? Are you having fun?’ Which I definitely am now that I’m behind the camera and writing and have definitely found my path and my purpose,” Park says.

When I mention “The Secret Life of the American Teenager,” the ABC Family teen drama in which she played the role of stuffy teenager Grace Bowman for 121 episodes, Park laughs. “How embarrassing,” she says, encouraging me to finish the question. What continues to draw her to stories about teenagers? And what was it like creating a new take on the way those kinds of stories are told?

“Even though we had a great experience working on this show, sometimes it’s difficult to write things for young people because it’s hard to make it feel authentic to that generation in that moment,” she says. “I wanted to make sure that I did that justice when I wanted to tell stories in that space, because as an actress, I didn’t always feel like that was the case. I didn’t always feel like I had a say or a voice as a young actress in the industry. So I want to create a different atmosphere that I would have loved to have been in when I was younger, that shows how smart, strong and talented all of these young people are.”

So what would she say to her younger self, what would she tell “young Megan” about filming “My Old Ass”? “Take in every second and enjoy it,” Park replies. “As cheesy as it sounds, it goes by so fast. It’s a summer you’ll never fucking forget. And it feels so exciting that we have it on camera now. It’s like a time capsule that we can look back on.”