The Long Dark Tea-Time of the Soul is a 1988 humorous fantasy detective novel by Douglas Adams. It is the second book by Adams featuring private detective Dirk Gently, the first being Dirk Gently's Holistic Detective Agency. The title is a phrase which appeared in Adams' novel Life, the Universe and Everything to describe the wretched boredom of immortal being Wowbagger, the Infinitely Prolonged, and is a play on the theological treatise Dark Night of the Soul, by Saint John of the Cross.