From an Alzheimer’s patient in his 80s in “Remember” (2022) and Sunyang Group’s founder Jin Yang-chul in “Reborn Rich” (2022) to veteran detective Kim Taek-rok in “Shadow Detective 2,” Lee Sung-min is on a roll with unique elderly characters.

Though the diversity of portrayals was a huge challenge, Lee was certain that the roles would become a assets in the future.

“I had a chance to feel what it would be like to perform 10 to 20 years in the future. It was an indirect experience of my future. I personally felt that the experiences were priceless,” Lee said in an interview with a group of reporters at a cafe in Samcheong-dong, Seoul, Monday.

“But, Yoon Je-moon, who co-starred (with me) in both ‘Remember’ and ‘Reborn Rich,’ jokingly said that I should move on from being a grandfather all the time. Maybe, now is the time to do something new,” he said.

Lee added that he would play elderly characters once again, when he really becomes old.

“I'm not thinking of a specific role that I want to play in the future. I simply love to explore new stories and play diverse characters,” he said. “I am aware that the number of options will be limited as I get older, but I want to entertain my fans with interesting characters as much as I can. And (I think) this is my duty as an actor.”

In Disney+’s latest crime thriller “Shadow Detective 2,” Lee plays Taek-rok, a detective on the verge of retirement, who has been framed for a murder he did not commit.

While the previous season presented a lot of action, the sequel focuses more on Taek-rok’s psychological battle with the mysterious villain.

“The viewers might think that I enjoyed the static performances in season 2, because it looks easier than the action scenes. But, I prefer the breathtaking chase scenes and fighting criminals," the actor told The Korea Herald.

Lee was a little concerned about the second season, because Taek-rok does not get involved in spectacular physical action, chases or explosions. He felt that the viewers may feel less thrilled with the latest version of "Shadow Detective."

The actor thanked director Han Dong-hwa, who put an amazing effort and turned the series into a stunning spy series.

Lee also pointed out some of the parts that he could have improved to deliver a more entertaining project to the viewers.

“Taek-rok’s narration was one of the unique features in the series. I really enjoyed Taek-rok’s monologues, when he was talking with his friends and possible villains. He shared the eyes of suspicion and his psychological states with the viewers in season 1. I wish we could have done more of those in season 2 as well,” Lee said.

After starring in a multi-season drama series for the first time in his 36-year career, Lee felt the actors and the staff created unparalleled teamwork.

“We spent a lot of time together. It brought us great synergy," Lee said.

"I know nothing about ‘Shadow Detective’ season 3, but I think we can do something amazing if we work together one more time. It was a great pleasure to work with talented actors and staff,” he said.