Excedrin bottles were investigated by police after Susan Snow died from taking pills poisoned with cyanide. Investigators later found a chemical used to clean the algae in fish tanks mixed in with the cyanide and, through pet store records, traced the chemical to suspect Stella Nickell. Stella's husband Bruce died from poisoning and, with this new information, they re-opened the investigation of his death. Stella had increased Bruce's life insurance shortly before his death. Because the death had to be accidental in order to receive the insurance pay out, she poisoned several other bottles, waiting for a second case to occur.