In the Netflix drama “The Frog,” actress Go Min-si, 29, who plays the lead character Yoo Sung-a, desperately pleads over the phone to the pension owner, Young-ha (portrayed by Kim Yoon-seok), who has disappeared without a trace.

“Ajeossi (Mister)….. When are you coming back here?”

Her face is smeared with blood — evidence of a recent killing. Is there a more chilling way to plead for help?

In this drama, released on Aug. 23, Go unveils a portrayal of madness unlike anything seen before. The “sweet intern Go Min-si” from the tvN variety show Jinny’s Kitchen 2 — who was so concerned about making mistakes with food orders that she avoided drinking water to minimize bathroom breaks — is nowhere to be found.

Instead, she transforms into a character who kills without remorse, embroiled in a high-stakes cat-and-mouse game with Bomin — a former violent crimes detective now serving as a police chief, played by Lee Jung-eun.

In an interview with the Hankook Ilbo, Go said, “I was really curious about how international viewers would react, and 한국을 they said, ‘A rare Korean female villain has appeared in a crime thriller.’”

Go’s daring performance in “The Frog” showcases her as an unpredictable actor, like a rugby ball that could bounce in any direction.

The character of Sung-a in “The Frog” posed a substantial challenge for Go.

“I had a meeting with Director Mo Wan-il that felt almost like an audition. I felt the character’s image, as described in the script, was quite different from my usual roles. Since it was such a departure from what I’ve done before, I thought the director might find it difficult to choose me.”

She even recalled, “This project might be problematic even if I get cast,” due to the challenging nature of developing the character.

Ultimately, Go was cast in the role of Sung-a. She revealed that working on “The Frog” allowed her to discover a new side of herself, and added, “It was a project I truly enjoyed filming.”

Sung-a is a mysterious character with a past unknown to the audience. Go said, “When I read the script, I wondered what experiences Sung-a went through to become who she is now.”

She continued, “I wondered, ‘Why did she marry Jae-sik (Jang Seung-jo), and why did she do such a cruel thing to a child?’ I got some answers, but I felt that a killer shouldn’t be understood. Our drama is about the victim’s story, after all.”

She believed that offering the murderer a detailed background would be inappropriate, which is why Sung-a’s history was not included. Nonetheless, Go emphasized that Sung-a is a character marked by “immense emptiness” and a profound sense of self-pity.

To portray Sung-a convincingly, Go decided to reduce her weight to 43 kilograms. “While looking beautiful on screen is important, I felt it would be more effective if my spine was visible, giving me a more eerie appearance.”

She added, “Even if it’s just a brief scene, I wanted it to help bring out Sung-a’s character. I aimed to capture a raw, animalistic feeling.”