@Tersione@BalrogDeMorgoth@Feeder I think the explanation is bollocks. The detective is wrong. A couple chapters ago we saw someone looking at Ji Young from inside a car behind him. Someone who had the same hair colour and style as he and the imitator. It's a separate person.
Split personality isn't something that you use as first hypothesis. Even your gut feelings don't matter in cases. But I guess author has to help out policemen somehow.
I thought the detective is a millenia-old cliche of idiot supervisor or is attempting to jeopardize the investigation wholesale.
Turns out he's not the former and if he's doing the latter - at least he's doing it in style. Good job, author.