When Cleveland Brown takes to throwing eggs at people to extract revenge for slights against Donna, an egg he pitches at Lydia causes her to drop over in front of a maid where she is declared dead. After the coroner confirms the cause of death is the egg, Cleveland is sent to prison. However, LeVar Brown has doubts about Cleveland's trowing ability and proves that he couldn't throw hard enough to hurt Lydia. Going to the morgue with Rallo and Cleveland Brown Jr., the coroner denies them access to Lydia's body as well as denying Junior a bite of his peanut butter sandwich. After LeVar spills coffee on the coroner's expensive shoes, they slip into the back and discover that Lydia died of an allergic reaction to peanuts.
After Lydia's earlier spat with Fern Stapleton over her peanut brittle, she becomes the prime suspect but find she has an alibi. Investigating they find a broken window and footprints leading them to confront Mr. Waterman over the murder of his wife. Mr. Waterman insists that he is also allergic to peanuts and when LeVar tests his theory by splashing him with peanut oil, Waterman collapses and the coroner has him rushed into an ambulance after attempting mouth-to-mouth resuscitation. As they cackle about getting away with the ruse, they find they have been discovered by Donna and the family posing as the driver with a recording of their confession. LeVar had deduced that the expensive shoes were a gift from Mr. Waterman and the coroner's peanut butter sandwich proved Mr. Waterman wasn't really allergic after the coroner's attempt at mouth-to-mouth.