Jeong Hae-deun, who is part of Ja-yu’s inner circle, is revealed to be a spy. In Blood Free, Park Ji-yeon plays Jeong Hae-deun.
Jeong Hae-deun is one of the few people who have worked closely with Ja-yu since she left her job as a lawyer to work for Ja-yu at her request.
Hae-deun is almost like Ja-yu’s assistant; she is always aware of Ja-yu’s whereabouts and plans, which she takes full advantage of.
It is only later that Ja-yu and Chae-woon discover that Hae-deun is a mole planted by DORSON to uncover Ja-yu and BF’s secrets.
The spy among Ja-yu’s people
All the while Hae-deun is working for Ja-yu, she keeps giving away company secrets not just to Chairman Seonu but also to Lee Mun-gyu.
She takes photographs of BF’s labs and sends those to Lee Mun-gyu. Apart from that, she is the one who convinces Professor Kim Sin-gu to join the support group.
There, Professor Kim meets a man who introduces himself as Park Sang-min. The man brainwashes him against Ja-yu.
Professor Kim then betrays Ja-yu, and when Ja-yu comes close to catching him, he is killed by the people who orchestrated the whole thing.
Hae-deun also has a hand in getting a protestor to take his life by jumping on top of Ja-yu’s car. This results in Ja-yu deciding to hire a bodyguard.
Once again, through Hae-deun, Lee Mun-gyu is able to get Chae-woon, who is to spy on Ja-yu for him, hired as her bodyguard.
While Hae-deun knows everything about Ja-yu’s activities, she is kept in the dark about the research work on cultivating human organs that goes on in the basement.
Hae-deun does not have access to the basement, but as she is quite sharp, she manages to find out the nature of the work happening there.
Hae-deun gets caught
When Ja-yu’s second bodyguard, Ho-seung, questions Hae-deun about Ja-yu’s schedule, Hae-deun learns that Ho-seung and Chae-woon plan to go to the welfare center to investigate.
She alerts the man who brainwashed Professor Kim, resulting in Ho-seung’s murder when he catches the man.
Ho-seung’s death burdens Hae-deun with guilt, though not enough to stop spying. She realizes that Ja-yu will now find out about her betrayal.
She thinks about running away before Ja-yu catches her, but Chairman Seonu convinces her to stay, as there is no evidence linking her to the murderer.
The fact that she is one of the people who knows about Ho-seung and Chae-woon’s plans makes Ja-yu and Chae-woon suspect her.
On San then lures Hae-deun into a trap and catches her leaking the secrets to Chairman Seonu red-handed.
Instead of handing her over to the police, Hae-deun is kept at BF and tortured, but she refuses to reveal the identity of the murderer and the people she is working for.
Hae-deun pleads with Ja-yu to hand her over to the police, and Ja-yu reports her spying activities, but she also tells the police that Hae-deun has gone missing.
Ja-yu plans to keep Hae-deun at BF until she confesses or until they extract the truth using their technology, but it is not going to be easy to break Hae-deun.
Also Read: Yun Ja-yu: Blood Free character explained