Darnell and Darnell present the first, complete English translation of the ancient Egyptian books of the Netherworld, originally composed during the middle of the second millennium BCE. These texts contain philosophical and theological speculation about the inner workings of the cosmos, particularly the events of the solar journey through the twelve hours of the night. The Netherworld Books describe one of the central mysteries of Egyptian religious belief—the union of the solar god Re with the underworldly god Osiris—and provide information on aspects of Egyptian theology and cosmography not present in more widely read texts, such as the Book of the Dead.