When Agatha Raisin returns home after a sojourn in the capital, she finds a new woman ensconced in the affections of her attractive bachelor neighbor, James Lacey. The newcomer, Mary Fortune, is superior to Agatha in every way, especially when it comes to gardening. With Carsely Open Day approaching, Agatha longs for some fascinating crime to remind James of her genius for investigation and to distract him from Mary. Soon a series of assaults on the finest gardens is followed by murder when Mary herself is discovered buried upside down in a terracotta pot. Agatha immediately starts digging up all the dirt she can on the victim-but she has a secret of her own.