In "Signal" it was shown that Jo Jin Woong was the police officer that had taken on the case of Lee Je Hoon's older brother.
On the 9th episode of tvN Friday/Saturday drama "Signal" (script Kim Eun Hee, director Kim Won Suk) broadcast on Feb. 19th, Park Hye Young (played by Lee Je Hoon) and Cha Soo Hyun (played by Kim Hye Soo) had a conversation.
On this day, Cha Soo Hyun saw that Park Hye Young was continuously showing interest in Lee Jae Han. She said, "Then again, all the incidents that you have shown interest are related to Lee Jae Han."
At this, Cha Soo Hyun said, "If your hometown is In Jo then you must know about the serial rape incident there. That was also covered by Lee Jae Han."
Park Hye Young said, "That detective looked into that incident too?" Witht hat, he saw that this person was the one who pointed to his brother to be a rapist.
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.
