Psychopath Diary () is a 2019 South Korean television series starring Yoon Shi-yoon, Jung In-sun and Park Sung-hoon. It aired on tvN from November 20, 2019, to January 9, 2020.

Synopsis Yook Dong-sik (Yoon Shi-yoon), an analyst who works at Daehan Securities, has a timid personality. He can't even get angry at the people who look down upon him. One day, shortly after failing on his attempt of suicide, he witnesses a murder. He unintentionally picks up a diary belonging to the murderer, on which was written the log of his murders. He flees with the diary, but he is accidentally hit by Police Officer Shim Bo-kyung's (Jung In-sun) patrol car which causes him to suffer from retrograde amnesia. Due to the diary in his possession, Dong-sik mistakenly believes he is a psychopath. Since that moment, his behavior started to change. Bo-kyung, who got involved with Dong-sik, decides to catch the serial killer.

Meanwhile, Seo In-woo (Park Sung-hoon), the director and son of the chairman of Daehan Securities where Dong-sik works, turns out to be the heartless psychopath serial killer. He loses his diary when his 6th victim, a homeless old man tossed his diary away. He feels insecure ever since, He is obsessed and in love with DongSik .

Cast Main Yoon Shi-yoon as Yook Dong-sik, a timid and pushover man who works as a clerk at Daehan Securities. His weak personality begins to change when he perceives himself as a killer. Jung In-sun as Shim Bo-kyung, an officer in a patrol station. Park Sung-hoon as Seo In-woo, the real psychopathic serial killer who is also the director of Daehan Securities where Dong-sik works at.

Supporting People around Yook Dong-sik Lee Han-wi as Yook Jong-chul, Dong-sik's father. Hwang Geum-byul as Yook Ji-yeon, Dong-sik's older sister. Kim Gyul as Jo Yong-gu, Dong-sik's brother-in-law. Jung Su-bin as Yook Dong-chan, Dong-sik's younger half-brother. So Hee-jung as Na In-hye, Dong-sik's step-mother, Dong-chan's mother. Heo Sung-tae as Jang Chil-sung, a gangster who lives at Unit 708. He later addresses Dong-sik as his 'Big Boss' after mistakenly believes him to be a serial killer.

People around Shim Bo-kyung Choi Sung-won as Heo Taek-soo, Bo-kyung's partner. Kim Myung-soo as Shim Seok-gu, Bo-kyung's father who is a former investigator police. Lee Kan-hee as Lee Suk-yeon, Bo-kyung's mother. Lee Hae-young as Officer Ryu Jae-joon

People around Seo In-woo Park Jung-hak as Seo Chung-hyeon, In-woo's father who is the chairman of Daehan Securities. Yoo Bi as Seo Ji-hun, In-woo's step-brother and managing director of Daehan Securities. Yoon Ye-hee as Kim Eun-shil, Chung-hyeon's wife and Ji-hun's mother. Kim Hye-na as Seo Ji-eun, In-woo's step-sister. Lim Il-gyu as Kim Chan-il, In-woo's brother-in-law. Han Soo-hyun as Kim Mu-seok, former detective who now works for In-woo.

People at Daehan Securities Choi Dae-chul as Gong Chan-seok, the manager of Team 3 and Dong-sik's boss who is selfish and rude. Kim Ki-doo as Park Jae-ho, Dong-shik's cunning team member who claims to be his best friend. Jo Shi-nae as Han Jung-ah, Dong-sik's colleague. Lee Min-ji as Oh Min-joo Choi Tae-hwan as Shin Seok-hyun Hwang Sun-hee as Jo Yoo-jin

Others Gu Ja-geon as a bully

Special appearances Jung Hae-kyun as Kim Myung-gook, a homeless man. ( 1–2) Yura as a girl with a dog in park (Ep. 2) Nam Jung-hee as murder victim (Ep. 2) Jo Yoon Ho as Chil-sung's junior (Ep. 2) Han Ji-eun as a woman with a big guy (Ep. 2) Yoon Ji-on as Joo Young-min (Ep. 4–5) Lee Hyun-woong as Oh Myung-dal (Ep. 12–13, 16)

Production The first script reading was held in August 2019 in Sangam-dong, Seoul.

Original soundtrack

Part 1

Part 2

Viewership

+ Average TV viewership ratingsOriginal broadcast dateAverage audience share(Nielsen Korea)Nationwide Seoul 1 November 20, 2019 1.766% 1.730% 2 November 21, 2019 3 November 27, 2019 1.928% 2.057% 4 November 28, 2019 2.206% 2.174% 5 December 4, 2019 2.368% 2.507% 6 December 5, 2019 2.212% 2.346% 7 December 11, 2019 2.424% 2.866% 8 December 12, 2019 2.299% 2.782% 9 December 18, 2019 2.014% 2.099% 10 December 19, 2019 1.693% 1.954% 11 December 25, 2019 1.708% 2.025% 12 December 26, 2019 2.295% 2.718% 13 January 1, 2020 1.939% 2.213% 14 January 2, 2020 2.423% 2.633% 15 January 8, 2020 2.685% 2.762% 16 January 9, 2020 Average In the table above, the represent the lowest ratings and the represent the highest ratings. This series aired on a cable channel/pay TV which normally has a relatively smaller audience compared to free-to-air TV/public broadcasters (KBS, SBS, MBC and EBS).

References

External links