Winna returns to her Colorado hometown and her father's last residence, an 87-year-old mansion built by his father, to settle his estate.

As Winna shares memories with her married daughter, reconciles with her disinherited sister Chloe, and becomes reacquainted with old classmates, the old house gives up its secrets. A handwritten will, old love letters, an unfinished story in a notebook, and a diamond ring hidden among her childhood marbles call into question everything Winna knows about her beloved grandmother.

Then come footsteps on the stairs, numerous break-ins, her car's brake failure on a mountain road, a fall down the basement stairs. Someone is trying to kill Winna. She can't begin to think it is her sister or Todd, Chloe's handsome new husband. Could it be her high school boyfriend John or the local handyman she's hired?

The House on Seventh Street was inspired by the Nancy Drew mysteries the author loved as a girl.