Nancy and the Drew Crew learn that they have a new battle on their hands. George's strange behavior leaves Nick feeling unsettled. Carson makes Nancy an offer she can't refuse.

On the evening of Horseshoe Bay’s annual Harvest Carnival, the body of a mysterious young man is discovered on the Hudson carnival grounds. The Drew Crew is drawn into the case by a host of confounding clues surrounding a new menace terrorizing the town – a killer who has an enigmatic connection to none other than Nancy’s newest foil: Temperance Hudson.

While serving on a jury, Nick realizes that one of his fellow jurors may be the next target of the Frozen Hearts Killer.

Nancy searches for a missing person targeted by Temperance, who has also placed a fatal hex on the kids of the Youth Center. With the solution to the Frozen Hearts mystery almost in their grasp, a shocking reversal puts the Drew Crew in the crosshairs.