Tamberry

If I remember correctly his dad had been stealing his sister's beauty cosmetics and giving them to the women he worked with and one of those was the red nail polish. I think it was a red herring to make us think that the dad was the killer.

This show is so great! I'm watching it with my parents and they keep sobbing haha

Was it explained what happened to Jae Chan and Seung Won's mother? Why did Seung Won live with Jae Chan and not her?

Personally I think Old Boy is the best of the three.