The book begins when the recently orphaned Lewis Barnavelt moves to the (fictional) town of New Zebedee, Michigan, to live with his mysterious uncle Jonathan Barnavelt. Jonathan turns out to be a mediocre, though well-intentioned, wizard, while his next-door neighbor and good friend, Florence Zimmermann, is a far more powerful good witch. Jonathan's house was previously owned by Isaac and Selenna Izard, a sinister couple who had dedicated their lives to evil magic, and plotted to bring about the end of the world. Before dying, Isaac constructed the titular clock that he hid somewhere inside the walls of the house, where it eternally ticks, still attempting to pull the world into the magical alignment, which would permit him to destroy it.
Lewis manages to befriend a local boy named Tarby, who is everything he is not—popular, athletic, thin, and so on—but the two soon begin to drift back apart. Lewis tries to win Tarby back by demonstrating how to raise the dead in the local cemetery on Halloween but only succeeds in releasing Selenna from her tomb. An escalating series of encounters with the sorceress' ghost builds to a final confrontation in the basement of Jonathan's house, where Lewis must summon up his courage and prevent her from finishing her husband's work and bringing on Doomsday.
As the story ends, Lewis announces that he has found a new friend, a girl named Rose Rita Pottinger.
- The Figure in the Shadows (1975)
- The Letter, The Witch, and The Ring (1976)
- The Ghost in the Mirror (1993)
- The Vengeance of the Witch-Finder (1993)
- The Doom of the Haunted Opera (1995)
- The Specter From The Magician's Museum (1998)
- The Beast Under the Wizard's Bridge (2000)
- The Tower at the End of the World (2001)
- The Whistle, The Grave, and The Ghost (2003)
- The House Where Nobody Lived (2006)
- The Sign of the Sinister Sorcerer (2008)
The book was used as the basis for one of the three segments in the 1979 television anthology Once Upon A Midnight Scary, hosted by Vincent Price.