Top 7 in Top 10 detective Kdramas you must watch once in your life.
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The show started 15 years ago with the murder case of a young girl. Park Hae-yeong, then an elementary school student, was a witness to the crime, and began to lose trust in the police because after a period of investigation they still could not find the culprit. Fast forward to the present time, Hae-yong joins the force and becomes a crime detective. He eventually finds a walkie-talkie that somehow helps him contact Detective Lee Jae-han, a wonderful man who was. Together they team up to solve many other unsolved cold cases even though they live in different eras.
Main actors: Lee Je Hoon, Kim Hye Soo, Cho Jin Woong