 The title is a phrase that 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.The novel is named for that time on a Sunday, after afternoon but before evening, as the week-end had finished but the week had not yet begun, that occurred to Adams as a listless limbo of the working man