Summer, 1941. Murdoch, Illinois, in the Corn Belt of Ashford County. With the nation on the verge of a second World War, a young man finds work at the house of the wealthiest family in town. Harold Albright has a simple job: keep quiet and do as he's told. This decree comes from Alice Tandy, the no-nonsense head of the housekeeping staff. The homeowners, Donald and Hannah Brenton, are urban transplants seeking a quieter lifestyle, who keep their business mysteriously concealed. They are also the proud parents of two daughters: Sally, who has recently married, and Lily, who supposedly took ill after the wedding, and has been quarantined to the attic.

When word spreads that three bodies have been found mutilated, Donald offers to help authorities seek the killer. He coaxes Harold into assisting and winds up leading the naive young man and the dutiful Alice into a labyrinth of deceit, madness, and murder. Lingering in the periphery is the shadowy figure of a local legend commonly known as the Slingerman, who some believe is behind the heinous crimes. Harold, who has heard stories of the creature since his cradle days, has his doubts until the ominous figure begins manifesting itself to him. But is a ghoul from beyond the grave truly to blame or could the truth be grounded in a more tangible reality—and one much closer to home?