Nobody Is Innocent

Alfred Hitchcock was a master of this principle, the idea that every character in a story carries their own dark secrets, their own special form of guilt. Who can forget the opening sequence in Psycho as Janet Leigh's character drives through the rain, plagued with second thoughts about the $40,000 she has just embezzled from the bank where she works, second thoughts about the wisdom of running off with the married man she has been having an affair with?

In Peter Straub's Ghost Story, there is an entire club of men who carry around the hidden secret of a crime they committed in their youth.

In The Shining, Jack Torrance is racked with misgivings about his inability to control his temper, and his wife is racked with guilt over the thought that she hasn't provided Danny with the stability and safety that every mother feels her child deserves.

This notion of guilt is an effective tool for several reasons. (1) It allows the author to rake up all sorts of uneasy feelings within the character's internal monologues, (2) It draws in the reader, as they sympathize with the internal struggles and moral dilemmas faced by the characters, and (3) It creates vulnerability within the character, the sense that they may not be immune from some form of harsh future judgment and punishment.