MANILA — Jun Ji-hyun admitted to feeling pressure over joining the hit Netflix series "Kingdom" late in its run, which motivated the South Korean actress to do better in her new role.

Jun's character, Ashin, was introduced in the series through a brief appearance in the second season finale but much about her remains a mystery.

"Being able to participate at a later point in time for a series that I love so much, I have to say that there was quite a significant level of pressure for me," Jun said in a press conference on Tuesday for the special episode "Kingdom: Ashin of the North."

"I deliberately tried to feel that positive pressure so that I could do better. I didn't want to make it look like I was just kind of joining and enjoying the ride," said the award-winning actress, who is also known for starring in the film "My Sassy Girl" and the series "Legend of the Blue Sea."

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The special episode, set to drop on Friday, July 23, will explore the backstory of Ashin, who comes from the northern regions of South Korea's Joseon dynasty. It will also feature the origin of the resurrection plant that triggered the zombie outbreak in the first two seasons.

Kim Eun-hee, who wrote the series, said the character of Ashin was developed during the early stages of the second season.

While doing research on north Joseon, Kim came across a marginalized group living in the area during the period.

"I decided to take an interest in that aspect (the marginalized people) and throughout that process, this character Ashin was crystallized," she said in the same conference.

Kim also said "Kingdom" fans who are looking forward to a lot of action scenes in the special episode "might slightly think it's not really what they expected."

Director Kim Seong-hun, meanwhile, said the show's international popularity also pushed the production staff to put more effort into the series.

"Now, because we know how many people are waiting for the series globally, I think more effort was put into meticulous investigation of historical correctness and also each of the props," he said.

In preparing for the role, Jun said she focused on interpreting Ashin's "han," a unique Korean concept of an emotion similar to anger.

"I tried to focus mostly on how to interpret the personal anguish and hurt... how to interpret that emotion into wanting to avenge for the whole land of Joseon," she said.

Jun also shared that she was never afraid to be around the actors playing the undead. In fact, she was even excited to meet them when she began shooting for the period horror.

"I begged them for pictures as well so I was able to take pictures with the zombie actors and really brag about it to my friends and family," she said.

Actor Park Byung-eun joins Jun for the special episode, reprising his role as Min Chi-rok, who headed the Royal Commandery and fought against the zombies in the second season. Actress Park Si-ah, meanwhile, plays a young Ashin.

"Kingdom," which follows a zombie outbreak amid a politically turbulent Joseon kingdom, first premiered on Netflix back in January 2019.

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