When actor Cho Jin-woong sets foot on a set, it means he is totally ready to transform himself into his character.

“Before we start shooting, I have to figure out everything about my character. Otherwise, I would keep on bugging my directors,” Cho said. “When I am on a set which is fully decorated by the art team with my costume on, I have to be completely ready to be the character I am playing,” Cho said. “Until I reach that point, I race to this goal, just like my character Kang-yoon.”

Park Kang-yoon, a police officer in Cho’s new movie “The Policeman’s Lineage,” directed by Lee Kyu-man, is goal-oriented. He is not afraid of conducting illegal investigations or even working with criminals to make an arrest. He later finds out that his subordinate Min-jae (Choi Woo-shik) is secretly keeping an eye on him and has been reporting his wrongdoings.

Even if it is just a single line, the 45-year-old actor said he tried to understand it fully before he performs to deliver a realistic and believable performance.

“There is a scene of Kang-yoon drinking soju with Min-jae. Kang-yoon says what I considered as a controversial line in that scene,” Cho said. “He says when conducting an investigation, no matter what measures he takes, they are all legal. I thought the line was too extreme at first.”

Cho explained that through discussing his character with the director, he could figure out that Kang-yoon strongly believes that he is doing everything for the greater good.

“That scene was necessary to show Kang-yoon’s strong belief,” Cho said.

“By the way, we drank actual soju in that scene.”

As a co-star in the new film who witnessed the whole process of how Cho works on the set, Choi praised him in a previous interview by revealing that Cho was always on his bucket list of actors he wanted to work with.

When asked about Choi’s compliment, Cho replied with grace: “I am probably one of many on his list.” Then Cho talked about his experience working with “Parasite” star Choi.

“Since Choi Woo-shik is so pretty, I was not sure about him playing this role at the beginning, but I could see him grow. I think this is because he understands the character well,” Cho said. “I was especially impressed by the expression in his eyes. It was amazing.”

“The Policeman’s Lineage” is based on a Japanese novel of the same title written by Joh Sasaki. Cho said that he has still not read the original novel yet, but he met with the author while filming.

“The author came to our filming site. He gave me a signed book. It was too thick,” Cho said. “I will read it when I am traveling.”

Sasaki’s translated book in Korean is 684 pages long.

“I could feel that he has special affection in our film. The author also told me that he enjoyed watching ‘The Handmaiden’ that I starred in, so I gave him a signed DVD,” Cho said. “I have done a few films that are based on a Japanese novel like ‘Suspect X,’ but it was the first time that the author actually came to the set.”

“The Policeman’s Lineage” is now in local theaters.