Cast
Ji Sung as Jang Jae-kyung, a detective of the Narcotics Team at Anhyeon Police Station
Jeon Mi-do as Oh Yun-jin, a social affairs reporter of the Anhyeon Economic Daily
Kwon Yul as Park Tae-jin, a prosecutor at Ahn Hyun District Office
Kim Kyung-nam as Won Jong-soo, Geumhyeong Group's successor
Yoon Na-moo as Park Jun-seo, the central figure in the incident
Jung Yoo-min as Choi Ji-yeon, Jun-seo's wife
Jung Jae-kwang as Kim Chang-soo, Jae-kyung's teammate
Cha Yup as Oh Chi-hyun, Jong-soo's chief secretary
Jeong Soon-won as Heo Joo-song, CEO of Two Star Holdings, an insurance company
Park Geun-rok as Jung Sang-ui, a researcher at Geumhyeong Pharmaceutical
Jae-kyung is at Jun-seo's house when Tae-jin, the cheating man, enters using the password. Choi Ji-yeon makes an excuse, which is suspicious, but Jae-kyung pretends not to notice.
Because of Jae-kyung, Tae-jin and Ji-yeon part awkwardly and arrange to meet later at a café. However, they are caught by Yun-jin, hiding at the apartment entrance.
Yun-jin secretly eavesdrops on their conversation and learns that Tae-jin demands a password from Ji-yeon. Ji-yeon tells Tae-jin that she will give him the password once he gets a divorce.
After losing his firearm, Jae-kyung faces a crisis at the police station for not returning it. He manages to get a week's grace period with the help of a fellow sergeant.
Won Jong-soo, the vice president of Geumhyeong Group, presents to Chairman Won Chang-ho, following Tae-jin's coaching. The chairman is pleased but privately tells his son, Jong-soo, that he knows Tae-jin prepared the materials and instructs him to cooperate with Tae-jin.
Jong-soo's inferiority complex towards Tae-jin flares up again. Ultimately, Jong-soo collapses during the business plan presentation. Suffering from breathing difficulties, Jong-soo takes a mysterious pill and calms down.
To track the pills, Jae-kyung pretends to buy some himself.
After many twists and turns, Jae-kyung encounters Kim Chang-soo at the investigation scene, ending Episode 6 of "Connection."