Episode 7

["I remember the criminal 14 years ago" - Arcade Murder Case in Oncheon-dong, Busan] In July 2000, a horrific murder occurred in broad daylight at an arcade in Oncheon-dong, Busan, which was bustling with customers. The victim, who was a cashier at an arcade, was found inside a public bathroom with a knife stabbed eight times. The police dispatched to the scene secured a bloody note (fragmented fingerprint) presumably belonging to the criminal, but due to lack of evidence and fingerprint analysis technology that was incomplete at the time, it was eventually left as an unsolved case. And 12 years later, as the National Police Agency's automatic fingerprint search system (AFIS) technology developed significantly, the bloody fingerprints of the 'Busan Arcade Murder Case' were reassessed, and 12 years after the incident, a person matching the criminal's fingerprint 'hand' found Mr. Son, who was identified as a suspect, stubbornly denied the crime. To make matters worse, the original records and evidence from the investigation from 12 years ago were lost, and the re-investigation went through difficulties... And only after 14 years of the incident, the true culprit of the 'Busan Arcade Murder Case' was sentenced to life imprisonment. Just over a year before the statute of limitations expired. What is the smoking gun that played a decisive role in apprehending the criminal?