Suho plays the role of Crown Prince Yi Gun in MBN's romantic comedy series "Missing Crown Prince." Courtesy of MBN

Singer and actor Suho of K-pop group EXO ventured into the period genre series for the first time in his acting career with MBN's recent romantic comedy series "Missing Crown Prince," which concluded with its highest viewership rating of 5.1 percent, Sunday.

Singer and actor Suho / Courtesy of SM Entertainment

"I've always given my best effort in every moment, down to the smallest detail. During 'Missing Crown Prince,' I rarely spent time with friends. I would read the script even while eating and continue until I went to sleep," the actor told The Korea Times, during an interview at his agency, SM Entertainment, in Seongdong District, Seoul, Friday.

"That's how much effort I've put into it, so I have no regrets or disappointments. I feel relieved and much lighter at heart. However, it doesn't mean I'm completely satisfied. I will identify my shortcomings and areas for improvement as I move on to the next step."

The historical rom-com series, set in the Joseon Dynasty (1392-1910), revolves around fictional Crown Prince Yi Gun (Suho), who gets mistakenly kidnapped by Choi Myung-yoon (Hong Ye-Ji), the daughter of a royal doctor.

When Yi witnesses a scandal in the palace that jeopardizes his position as the crown prince, he is compelled to flee, with Choi by his side to assist. Despite their initial misunderstandings, the two develop an unexpected romance while navigating royal politics and dangers to save his father, his throne, and their own lives.

The 20-part series was led by famous director Kim Jin-man, who previously worked on smash-hit series like "Kill Me, Heal Me" (2015) and "The Greatest Love" (2011).

A scene from the series "Missing Crown Prince" / Courtesy of MBN

Suho said the director played a great role in getting him to take on his first period series.

"I initially aimed to tackle historical dramas once I gained more experience, focusing for now on lighter characters. However, when I learned that the director of 'Kill Me, Heal Me' would be leading the project, I became interested," he said.

Suho also noted that after the series aired, he began to be recognized by older viewers.

"It appealed to me that the historical genre series has a dedicated middle-aged viewership, which was one of the reasons I decided to join this project … Thanks to more (older viewers) recognizing me, I believe I will be able to take on more future projects as well."

The singer-actor said he studied countless period dramas to shadow the tone and dialect specific to the historical genre.

"I think I watched all the series with the crown prince character that came out over the past two years. When I first decided to do a historical series, I felt overwhelmed … I thought of the historical genre dialect as a new language. So I recited my lines over 100 times and practiced them in different versions, working with the director to find the best tone and delivery," he said, adding that his character allowed him to experience deeper emotions.

"Yi sacrifices himself a lot. Reading the script, I often thought, ‘Does he really have to carry this much?' or ‘Could such a person really exist in this world?' … Because I had to portray extreme emotions in extreme situations, I think my expressions have broadened and deepened. I feel I've grown a lot through this project."

A still from the series "Missing Crown Prince" / Courtesy of SM Entertainment

Aside from his acting, Suho is the leader of the popular nine-act group EXO. The group made headlines earlier this month when its unit, EXO-CBX, consisting of members Chen, Baekhyun and Xiumin, claimed their former agency SM Entertainment failed to honor the trio's rights for music distribution fees and unfairly demanded a share of the profit from its act. The trio left the agency after demanding to terminate their contract and reached a mutual settlement last year.

Suho shared that he only learned about the recent EXO-CBX issue from the news, expressing worries for the group's fans about the unexpected buzz.

"Other members, including myself, found out about (EXO-CBX's) press conference through the news. So I was quite surprised, confused, and disappointed. There was a similar incident last year, and ever since, I've been most worried about the fans … I want to say that I'm really sorry," he said.

"With Sehun and Kai being discharged from the military next year, there were plans we've been making with the agency, like a winter album … But it's not something I can promise definitely, so I'm worried."