A time-defying walkie-talkie connects 21st-century criminal profiler Park Hae-yeong with spunky detective Lee Jae-han in 1989. Together, they unravel mysteries from the past and present to reshape the future.
EPISODE 1
Episode 1
Profiler Hae-young finds an abandoned old walkie-talkie ringing inside a dump truck, parked outside a local police station; he hears the voice of a detective, who gives him evidence of an unsolved case of 15 years back.
EPISODE 2
Episode 2
Hae-young and Su-hyeon join the "Cold Case Task Force" which investigates the Kim Yun-jeong kidnapping case; Jae-han, tells Hae-young some clues from the year 2000.
EPISODE 3
Episode 3
Hae-young now realizes that Jae-han is from 2000, and that some consequences had changed the present day due to the clues from 2000; on a different note, the team works on the Gyeonggi Nambu serial murder case.
EPISODE 4
Episode 4
"Cold Case Task Force" continues the unwanted hunt for the serial killer from 2000; they finally have some substantial evidence in their hands.
EPISODE 5
Episode 5
Hae-young finds an old document that indicates Jae-han is missing; he continues to receive messages through the walkie-talkie.
EPISODE 6
Episode 6
Hae-young finds out the whereabouts and motives of the kidnapper of Sin Yeo-jin.
Lee Je-hoon
Kim Hye-soo
Cho Jin-woong
Jang Hyeon-seong
Jung Hae-kyun
Kim Won-hae
Lee Yoo-joon
Jung Han-bi
Kim Won-seok
Kim Eun-hee
