In a recent online post, veteran actress Kim Hye-soo shocked fans with a stunning display of her back muscles, once again showing her classic star power and shape at 55.

On September 23, Kim released a photo and a short remark on her own Instagram account, stating, "I didn't expect '王' to be on her back."

The photo demonstrates Kim tensing her back muscles while dressed in a snug-fitting exercise outfit.

As she presses down, the Chinese word for "king" (王) can be seen distinctly on her body, created by the outline of her toned muscles.

The post, as per Maeil Korea, quickly went viral, with fans and netizens praising her fitness motivation, as well as her noticeably lean and muscular body.

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Kim's fit into the form-cutting clothing also showcased her athleticism and received compliments on social media.

Kim, who has been considered one of the most iconic South Korean actresses for a long time, keeps fans in awe of her way of life.

Her commitment to health and strength training is observed from time to time through walking and underwater workout sessions, which she posts every now and then on social media.

Many have noted that she still boasts an impeccable "S-line" figure, a Korean term describing a voluptuous and well-proportioned figure.

Her most recent post arrives amid mounting anticipation for her return to the small screen. Kim Hye-soo will headline the upcoming tvN drama "Second Signal," which premieres in 2026.

Information regarding the drama is scarce so far, but those in the industry, as per Koreaboo, anticipate a strong performance based on Kim's proven acting chops and star power.

Both her physical transformation and comeback project were the subject of fan excitement.

"Kim Hye-soo never fails to amaze," one of the netizens noted. "She's a queen—literally and figuratively."

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