A psychological thriller with breathtaking production and aesthetics. A story that keeps us in suspense until the end with many twists and turns. We can suspect that the girl will not be the real culprit but even if we suspect it to the end, doubt is instilled in us (appropriate title).
The father/daughter relationship is quite interesting in its evolution from a childhood trauma to a need for trust. The interactions are slightly redundant but don't spoil the drama either.
On the police station side, I really liked the character of Yoon Gyung Ho who doesn't like our main protagonist, who just tries to do the job as best he can while remaining a human. The two assistant investigators are a little less interesting because each just has their bias and won't budge (both are wrong in their own way).