Jeong Yein Replaces Ha Young in 'The Trauma Code: Heroes on Call'

Jeong Yein, a former member of the girl group Lovelyz, is taking over a role in a Netflix hit. She will play nurse Cheon Jang-mi in Seasons 2 and 3 of "The Trauma Code: Heroes on Call," replacing actress Ha Young.

Netflix confirmed production of both seasons on Oct. 19 and revealed the cast. Actors Ju Ji-hoon, Choo Young-woo, Yoon Kyung-ho and Jung Jae-kwang will return from the first season. Jeong Yein joins them as Cheon Jang-mi, a nurse on the hospital's severe trauma team.

Season 1 premiered in January 2025. It follows Baek Kang-hyuk (played by Ju Ji-hoon), a surgeon who once treated patients on the battlefield, as he takes over the severe trauma team at a university hospital. After its release, the show reached Netflix's Top 10 in 63 countries.

The cast's chemistry was a big part of that success. Ju played Baek as a blunt, brilliant doctor. Choo played Yang Jae-won, a younger doctor who grows under Baek's guidance. The two clash over almost everything, but learn to trust and rely on each other when crises arise.

Cheon was a key part of the team, too. She worked alongside Baek and Yang, caring for patients and helping keep the trauma unit running. Ha Young played her as upbeat and energetic, and her scenes with the two lead actors brought a lot of the show's humor.

The role will now be played by Jeong Yein. Ha Young decided to step down from the upcoming seasons following a controversy over allegations concerning her great-grandfather's pro-Japanese activities during Japan's colonial rule of Korea. Jeong Yein was then picked for the role after auditions.

The biggest question is how well si Jeong Yein going to fit into the already established dynamic. Ju Ji-hoon, Choo Young-woo and the rest of the returning cast already built their characters' relationships in the first season. Jeong Yein will have to establish her own interpretation of Cheon while preserving the character's place within the team.

Even when a character remains the same, a change in actor can alter the feel of a familiar dynamic, so the key will be keeping viewers from feeling that something is off.

A recasting does not necessarily have to hurt a show, however. If Jeong Yein keeps what fans liked about Cheon while adding her own touch, she could bring new energy to the series. For a returning hit, that balance between continuity and change may shape how viewers respond to the next two seasons.