Let's see if this is a mystery story where the author themselves actually knows ahead of time who the culprit is, and plants logical hints to have the viewer get involved in solving the mystery.
Or if instead, this is a lazy mystery box plot where the author does not actually know who the culprit is, and just makes it up as they go along, hiding key details up to the very reveal of the mystery just to keep up the facade of a twist. Meaning the viewer would never be able to guess the mystery on their own.