Ten years after discovering her murdered uncle, Ena and Detective Hansaem must cooperate to stop a series of similar murders - each linked by strange puzzle pieces.
Episode 1
Detective Hansaem suspects Ena after she fails to remember anything about her uncle's murder.
Episode 2
A puzzle piece arrives on the same day as a murder, and Hansaem suspects it’s no coincidence.
Episode 3
Ena and Hansaem warily work together to solve the case.
Episode 4
A prime suspect emerges, but things aren't what they seem.
Episode 5
Another puzzle piece arrives, and a new murder case unfolds.
Episode 6
The meaning behind the drawings on the puzzle pieces is uncovered.
Episode 7
Hansaem makes a shocking discovery and becomes unsure of whom to trust.
Episode 8
As the investigation escalates, new suspects begin to emerge.
Episode 9
An unexpected suspect is arrested, shocking everyone involved.
Episode 10
A stunning truth behind the serial murders is revealed.
Episode 11
The final puzzle piece arrives will the team be able to catch the killer in time?