It all started with a cat and ended with murder. It happened like this: Annabelle Heyer, having gone in search of her missing pet, discovered the body of her owner in a neighboring house. Local police are ready to attribute the death of an old man to age-related problems. But the meticulous Annabelle finds out a strange circumstance: it turns out that recently more corpses have been found in their own homes than were found in the previous few years. What is this, a tragic accident or the activity of a murderous maniac? The police do not react to her statement in any way, and then Annabelle decides to unravel this complex tangle on her own...