Nicholas Johansson is just an ordinary eight-year-old boy the night his mom reads him the obligatory bedtime story in their Providence, Rhode Island home. Nicholas's mother tells him a tale about ghosts. She doesn't mean to scare Nicholas, but she delivers the tale with such vividness and enthusiasm, it leaves the boy a bit rattled. His life is never the same; that night a shadow chooses Nicholas and begins inhabiting his body and mind.

Nicholas lives in fear. By the time he is fifteen years old, he has survived twenty-two shadow attacks and avoided fifty other confrontations. He determines that some shadows are evil and kill, while others reach out for help. Some simply exist.

He also discovers that shadows see humans sometimes as clearly as humans see them. Nicholas becomes obsessed with what he finds and believes he has to reach out to them. The gap he tries to bridge between mortal and shadow worlds becomes his life's work. Along the way he creates a bond with Lynn, a female shadow. They travel an uncharted road leading them on an uncertain path in search of an answer-an answer to the how's and whys of the noises heard at night.