Sinal (2016)

Both dramas center on detectives and the murder cases they have to solve. In signal detectives try to solve a serial killer murder case like in blind.

They do have a different plot and story line, but the theme and the ambiance of these two drama are giving me the same feels. I also wanted to recommend Gapdong and I remember you, these are crime investigatory series too, which were a little bit lighter.

both are filled with suspense, twists, and different time portrayals. Both the male leads look for the criminal of serial killings of the past.

They each deal with solving crimes and busting the bad guys. In both Signal and Lookout (Th Guardians) there are several main characters that work in a team and have very deep, heart-wrenching backstories and goes/focuses on each their individual stories equally in different segments of the drama. Sooji and Haeyoung have strong similarities regarding the crimes that changed and ruined their lives. The villains are especially vile and will make your blood boil in both, LOL.

While Lookout is not as superb as Signal (among my top faves!), I still strongly recommend it because it is good and have paces that will have you on the edge of your seat until the very end.

Kim Eun Hee is the genius writer who wrote Signal and she is also the one who wrote Sign. Sign is also one of the best crime thriller dramas out there. If you are looking for something as good as Signal then you should definitely watch Sign and vice versa. Both dramas are blessed with excellent unforgettable plot, perfectly written characters and TOP actors. Sign has Park Shin Yang as the main lead and he is one of the best top notch actors. Both dramas gained high TV ratings and a must watch dramas.

If you like thriller, mystery & investigative story, Healer has it too. It's just balanced with comedy, romance & action. I noticed that the (old)... music used in ep1 in Signal was also used in Healer on their flashback scenes....
Music is added to have more thrilling feels....