When Hee-Joo (Shim Eun-Kyung) was 7-years-old her father was murdered. Her father worked as a detective and was working on a serial killer case. The killer, Ki-Bum (Kim Sung-Oh), was eventually arrested, but found guilty for only one murder.

15 years later, Ki-Bum is released from prison. Detective Dae-Young (Yoon Je-Moon) worked on the original case with Hee-Joo's father and he has not given up getting a murder conviction for his former partner. Meanwhile, Hee-Joo has waited patiently for Kim-Bum's release.

A little girl named Hee-ju who lost her father to a serial killer named Ki-bum 15 years ago awaits for his release. Ki-bum is released from prison after serving his sentence. Dae-young, a detective follows Ki-bum closely as he remains suspicious of the ex-con. A serial killer who has been waiting for his freedom, a detective who has been waiting for the killer’s release, and a little girl who has been waiting for something that remains a mystery...

The three are intertwined in a chaotic relationship and are met with an unprecedented series of events.