The Long Dark Tea-time of the Soul by Douglas Adams
The Long Dark Tea-Time of the Soul is a 1988 humorous detective novel by Douglas Adams, the second book to feature the holistic detective Dirk Gently. The story follows Dirk as he investigates a wealthy record executive's claims of being stalked by a seven-foot-tall, green-eyed monster. Dirk arrives hours late for the appointment to find the client decapitated, surrounded by police.