Fierce gang boss Jang Dong-su is violently attacked after a fender bender on a rainy night. After fighting back, he barely escapes, however his reputation as a feared leader is damaged beyond repair. The only way to restore his image is to find his attacker and exact revenge. Jang teams up with Detective Jung Tae-seok to find the assailant, but soon discovers the attacker is actually a serial killer. With no support from the police department, Detective Jung is forced to use gang boss Jang's resources in order to track down the killer. The two men must work together to find a man simply known as "K"....

South Korea’s latest thriller is here! Song Ji-hyo shows her own interpretation of the weird puzzle with her explosive acting skills! The little sister who had been missing for 25 years suddenly returns home, but her brother discovered that there is an unknown secret behind her......

The drama tells the story of Ji-o (played by Kim Rae-won), who is sought after by the world because of his special abilities, and Goo-reum (played by Lee Da-hee) who is the only crime squad detective who remembers his appearance. They both fight against a huge conspiracy together. Based on Darwin's "On the Origin of Species", the seed of life that can be traced back to the origin of all life forms is called "LUCA"....