In "Signal" Lee Je Hoon (played by Park Hae Young) used the walkie talkie to tell Jo Jin Woong (played by Lee Jae Han) that he had caught the real criminal.
On the 4th episode of tvN Friday/Saturday drama "Signal" (script Kim Eun Hee, director Kim Won Suk) broadcast on Jan. 30th, the team dealing with long term unresolved murders resolved the Kyeonggi serial murder incident.
Park Hae Young of 2015 called Lee Jae Han being very grateful. He said, "Officer, you gave me a piece of evidence and I was able to catch the culprit. The technology has developed a lot but even still, if there were no evidence, we would've lost the culprit again. You caught the culprit," and with that he thanked Lee Jae Han.
Meanwhile, "Signal" is about two detectives - one from the past and one from the present who communicate through walkie talkies to resolve long-time unresolved cases. As there are several desperate people who are trying to resolve old cases, detectives communicate with each other to share information and catch real culprits.
