From the jacket

How does it feel to be in a big department store after customers have hurried home and the lights have been darkened so that eeriness reigns over the vast reaches of the floors? To Linell Wynn, who writes sign copy for Cunninghams', such a scene has always seemed perfectly natural until the day that murder walks the floors at dusk.

The matter-of-factness of the police as they question people whom she knows, works with every day, does nothing to dispel the feeling that they are only temporarily holding back the powers of darkness. Evil has struck once--and evil is hovering, waiting to strike again. Steeling herself, giving herself courage against it, she is still unprepared when she stumbles upon death for the second time.

Things which have familiar everyday significance suddenly assume a strange unnaturalness and terror surrounds her. Before that terror can be vanquished, Linell, herself, stands face to face with death.