"Doors of the Night" by Frank L. Packard is a mystery novel written in the early 20th century. The narrative revolves around Billy Kane, a young man who has recently taken up the role of confidential secretary to the affluent David Ellsworth. The story begins on a troubling note as Kane senses that something is amiss with his employer, which ultimately leads to a shocking murder that complicates Kane's life and positions him at the center of a criminal conspiracy. The opening of the novel sets a tense atmosphere as Billy Kane paces in Ellsworth's lavish study, reflecting on the eccentric millionaire's odd behavior after dinner. His concern escalates when he receives a distressing letter suggesting he might not be trustworthy. When he discovers Ellsworth dead and learns that he has been framed for the murder, Kane's world spirals into chaos. With the police on his tail and his life hanging in the balance, he decides to go underground, adopting the persona of a notorious criminal known as "the Rat" in hopes of uncovering the truth behind the murder and clearing his name. This setup promises a gripping tale of intrigue and suspense as Kane navigates the darker streets of New York in search of justice. (This is an automatically generated summary.)