[7] A kidnapper disappeared 15 years ago without a trace leaving behind his dead victim, Seo-jin.

Five days before the case's statute of limitations expires, someone is found anonymously leaving a flower at the crime scene.

A few days later, another kidnapping takes place using the same method on a similar target.

Later it turns out to be the child's grandfather, Han (Song Young-chang), was the perpetrator of the first kidnapping 15 years ago.

The detectives find out, confront Han and revealed that the reason of his kidnapping 15 years ago was to collect the ransom money to pay for his daughter's heart surgery.