The Red Mist

From Introduction: A boxer lost in a psychic labyrinth, a monster that lurks within our own minds, and a mysterious book combine to drag the investigator into a bloody nightmare. This Cthulhu Confidential adventure casts an occult book dealer Phyllis (or Philip) Oakley as the player character. It can easily be adjusted to work with an original investigator of the player’s devising, or any of the ‘official’ trio of Dex, Viv or Langston). The place and date of the adventure are not specified, and none of the locations mentioned are real. Assume it’s set in New York in 1937 by default.