Nuances are shades of meaning or subtleties. Although barely perceptible individually, they add up to give a clear picture. In this way they help detectives both real and fictional to reach the correct conclusion.
Agatha Christie ‘s Miss Marple was great at picking up nuances. In “After the Funeral” she catches an imposter. The woman the imposter was impersonating used to cock her head to one side when she spoke. The imposter did so too but on the other side.
“By the pricking of my thumbs Something wicked this way comes.” This quote is from Shakespeare ‘s play Macbeth where one of the Three Witches is foretelling Macbeth’s career of evil.
Foretelling, premonition, hunches and intuition are all highly subjective phenomena. Yet they can serve as inspiration/adjuvants in helping a sleuth solve a case. These phenomena can often be seen in crime fiction , especially the cosy mystery kind.