Singer-turned-actor Yoona is no longer just known as a member of girl group Girls’ Generation. After debuting on the silver screen in the espionage film “Confidential Assignment” (2017) and starring in the hit comedy disaster film “Exit” (2019) which garnered over 9.4 million moviegoers, Yoona has established herself as a bona fide actor.

Now she takes on the role of La-hee, a pure-hearted high school student and the first love of a country boy in the film “Miracle: Letters to the President,” which hit local theaters last week. The film is set in the rural Bonghwa County, North Gyeongsang, in the 1980s.

“This was the first pure, bubbly romance movie I have starred in,” the actor said during a recent video call interview will the JoongAng Ilbo, an affiliate of the Korea JoongAng Daily.

“I didn’t feel particularly pressured that this is my first film since ‘Exit,’” said Yoona. “I only thought about what I want to do and what I want to show through this movie.”

The actor described “Miracle: Letters to the President” as “a film that heals you and fills your heart.” Bonghwa County, in which the story takes place, is a rural region in the southeast of Korea and was especially isolated until the 1980s as the town had no train station of its own.

In the film, a local high school student named Joon-kyung played by actor Park Jeong-min starts writing letters to the president, asking him to build a train station for the village. Joon-kyung eventually takes on the task himself and starts building a small station with the help of his family.

The story is adapted from the true story of Yangwon Station in Bonghwa County with a sprinkle of imagination. Yangwon Station, which is known as Korea’s tiniest train station, is also considered to be Korea’s first privately funded station because the locals raised money and built it by themselves in 1988.

Director Lee Jang-hoon of the 2018 romance film “Be with You” and screenwriter Son Joo-yeon wrote the script together.

Yoona plays the bubbly high school student La-hee who is in the same class as Joon-kyung. She is the one who notices his hidden talent in math and volunteers to be his “muse” who helps him follow his dream.

“She’s the one who notices Joon-kyung’s extraordinary abilities and leads him to fulfill his potential,” Yoona said. “She’s adorable and pure but also daring. I tried not to overthink while acting, but simply portrayed the exact emotions I felt while reading the script.”

One of the movie’s memorable scenes is when La-hee directly asks Joon-kyung “Do you like me?” in a thick Bonghwa dialect, leaving him flustered. What sounds like a clichéd line in any romantic comedy was brought to life by Yoona’s delivery.

“People around me told me that La-hee is actually like me,” the actor said laughing. “I did act in many scenes thinking, ‘I would probably also behave like this in such situation.’ I found every part of La-hee adorable.”

Yoona said the most challenging part of the filming was the characters’ thick Bonghwa dialect.

“I’m familiar with the Gyeongsang dialect, but Bonghwa dialect was different,” she said. “All the lines were so difficult, so I was always asking the dialect coach for guidance, even for minor lines.

“I referred to recordings of the script by people from that region, then compared my accent to theirs. My grandparents are from Yeongju [in North Gyeongsang], so the dialect that I heard from them since I was young helped me a lot too.”

Yoona said the most memorable scene to shoot was a cute date with Joon-kyung.

“Park is friendly and comfortable to be with,” she said. “Thanks to that, we were able to get along with each other on set. I think our chemistry was good and that really shows in our characters. Park made an effort to get closer with me so we could have that chemistry.”

Her costar Park has said in another interview that Yoona “acts freely,” proclaiming himself to be a fan and giving her the nickname “the star in my heart.”

“Park can handle all kinds of roles like an ever-changing chameleon,” Yoona said, and also gave him the nickname “Jeongmeleon,” a portmanteau of Jeong-min and chameleon.

“My fellow Girls’ Generation members told me their thoughts on the movie after watching it at the preview event,” she said. “Sunny said she enjoyed it and that the movie captures my cute side. Tiffany told me she cried her eyes out. Hyoyeon couldn’t attend because of another appointment on her schedule, but she says she is dying to find out what the movie is like.”

What does Yoona think is a better title for herself — “the center member of Girls’ Generation” or “actor?”

“I don’t want to miss out on either,” she said. “I’ll try my best to become a center among the actors as well then.”

BY NA WON-JEONG [kjdculture@joongang.co.kr]