If you want some action, crime, thriller, investigation, and a detective story, you've got to watch this too. Both of the teams are tasked to catch someone. In bad guys, POLICE +CRIMINALS. In hidden identity: SECRET AGENTS who go undercover. There are so many revelations. Expect the unexpected. The main character in hidden identity tries to seek revenge for his girlfriend's death. No love story except for the flashbacks. In bad guys, they identify and catch criminals to shorten their imprisonment. Plus, both series have the SAME DIRECTOR!