"Mr. Mercedes" is a gripping detective novel by Stephen King that revolves around a retired police detective named Bill Hodges. He is haunted by an unsolved case involving a mass murder that took place several years earlier when a deranged killer drove into a crowd, causing chaos and death. As Hodges grapples with his sense of purpose in retirement, he receives a taunting letter from the murderer, inspiring him to take matters into his own hands and reopen the investigation.
The narrative unfolds through the perspectives of Hodges and the elusive killer, known as Mr. Mercedes. As Hodges digs deeper, he is drawn into a dangerous game of cat and mouse, leading him to confront his own demons and the darker aspects of his past. Tension escalates as the story builds toward a showdown, showcasing King's skill in creating suspense and complex characters.