Signal (2016, tv)
Genres: Crime, Drama, Fantasy
Director: Unknown
Cast: Lee Je-hoon, Kim Hye-soo, Cho Jin-woong, Jang Hyun-sung, Jung Hae-kyun Lee Jehoon Kim Hyesoo Cho Jinwoong Jang Hyunsung Jung Haekyun
IMDb rating: 8.5
Overview:  Detectives from the present and a detective from the past communicate via walkie-talkie to solve a long-time unsolved case.