Insomnia

This novel is deeply integrated into Stephen King's multiverse, featuring significant ties to The Dark Tower series. Readers will find references and characters that expand the lore of that overarching narrative.

While it features a self-contained plot, the book's themes and certain character arcs resonate more deeply if you are familiar with King's broader fictional universe, particularly The Dark Tower. It can be read independently, but its connections enhance the experience.

Elderly widower Ralph Roberts begins waking progressively earlier—a side effect of being drawn into a war between cosmic forces King calls the Random (chaos) and the Purpose (order). Ralph discovers he can see auras, and that small beings called 'little bald doctors' manipulate the life-force of people in Derry. He is recruited as an agent of the Purpose to prevent a specific death.

Insomnia is deeply connected to the Dark Tower mythology. The cosmic framework of the Random versus the Purpose is part of the Tower's wider cosmology; a key character from the series is at the center of Insomnia's plot; and the novel explicitly references the Tower. King has called it an important Tower novel despite being set in contemporary Maine.

Ralph calls them that because of their appearance—small, bald, and precise. They are actually beings from a higher level of existence named Clotho and Lachesis (from the three Fates of Greek mythology), who cut human life-forces at their appointed end. Their antagonist is a rogue cutter named Atropos who kills ahead of schedule for his own purposes.

Critical reception has been divided. Some readers consider it an underrated gem for its intricate cosmology and the unusual choice of an elderly protagonist. Others find it overlong and too densely tied to the Dark Tower mythology for readers unfamiliar with that series. At 787 pages, it is one of King's more demanding novels.