Fans are divided over the casting of actor Choi Hyun Wook in the upcoming K-drama My Dearest Nemesis.

Choi plays the leader of a department store planning team who reunites with his first love, Moon Ga Young, in the upcoming series, which premieres February 17.

From Yang Hye Jin's hit Naver webtoon, the narrative follows the characters meeting online 16 years ago.

Moon played a high school senior three years older than her character, Choi. By the time the story catches up to the present, the characters are in their early 30s.

Attention has been drawn to the age gap between the actors and their respective characters.

One decade younger than his webtoon counterpart, Choi Hyun Wook is just 23 as of January 30.

With his co-star Moon Ga Young, who is just 28 years old, this creates a substantial 6-year age gap in real life.

After teaser photos from the drama were released, fans took to the social media platform Reddit to express doubts about Choi's ability to play an old character convincingly.

One viewer said: "He is too young for this character." Another fan said: "The age gap is throwing me off."

Here's what other fans are saying:

Despite the backlash, some fans remain hopeful for the series, and some defend Choi's actions against some of that negative discourse.

One fan tweeted, "He's a good actor." Another said, "I'm excited to see how he copes with this."

One of the highly anticipated new K-dramas premiering in February is My Dearest Nemesis, starring the ever-popular Kim So Eun.

So, the question remains whether Choi Hyun Wook's performance will convince the skeptics.