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
The drama Connection starts in the fictional city of Anhyeon. Jang Jae-kyung, a skilled and well-respected officer in the Narcotics Team at Anhyeon Police Station, is introduced.
Oh Yun-jin, a social affairs reporter for the Anhyeon Economic Daily, makes her debut in the story. Her introduction is rather unsavory, as she's depicted extorting money from a company by threatening to publish an unfavorable article. This unsavory act takes place in the very same restaurant where Jae-kyung is attempting to apprehend the notorious criminal Jang Cheol-gu.
Jae-kyung's pursuit of justice takes a ruthless turn when he confronts Jang Cheol-gu, the criminal responsible for severing his subordinate's Achilles tendon a month prior. Driven by a desire for retribution and a determination to protect his team, Jae-kyung shoots Cheol-gu in the Achilles tendon. This act of payback, while controversial, earns him recognition and leads to his promotion to inspector.
Later that night, Jae-kyung’s childhood friend, Park Jun-seo, visits him. Jun-seo tells Jae-kyung that he wants to make amends for past mistakes and leaves.
Back in high school, Jae-kyung had reported an incident and named Jun-seo as a witness. However, Jun-seo betrayed Jae-kyung by claiming he had not seen anything.
On the day Jae-kyung treats his team to a celebration dinner for his promotion, he is kidnapped from a restaurant bathroom after the gathering and found three days later on a subway station bench.
After regaining consciousness, Jae-kyung tries to catch Gong Jin-wook, a gang member, in the act of drug trafficking but is overpowered and loses his gun. He receives a message from a mysterious figure known as "The Doctor," which includes a video of Jae-kyung in a drug-induced stupor over the past three days. The Doctor is revealed to be the supplier of drugs to Gong Jin-wook.
Jae-kyung then learns that Jun-seo has died. What on earth is happening?
