Nine strange puzzle pieces. A series of nine meticulously planned murders. Who and why?

What really sold me on this series were the references to the golden age of detective stories in Britain. Agatha Christie is world famous and still well enough known, but when a writer mentions John Dickson Carr (the greatest for me) I am well impressed. And one could say there is a flavour of Carr in this series.

A young girl returns home to find her uncle murdered and a strange puzzle piece on the floor. But there is a hole in her memory, a detective is convinced she did the crime, but no charges are filed. Ten years she has become a criminal profiler, and re-unites with the detective when there are more murders and more puzzle pieces. Has she resumed the killing? What is going on?

A background theme of corruption is typical of Korean TV dramas, and a level of horror, but there is also an artistry here. The series hints at a sequel but don’t hold your breath.