Marge and Lisa get an addiction for listening to podcasts about crime. Homer and Bart visit Grampa at a retirement home. Grampa shows them his new girlfriend, Vivienne St. Charmaine. On the next day, the Simpson family watch news on television and learn that Vivienne is dead. Grampa is a prime suspect, but he says he does not remember what happened. Kent Brockman makes a podcast about the murder called "Guilty Grampa". The podcast makes everyone in Springfield think that Grampa killed Vivienne. Grampa thinks that he did do the murder and confesses. He is taken to jail. While the last episode of "Guilty Grampa" is being recorded, Dr. Hibbert says that Vivienne did not die. She went to a resort in Mexico so that Grampa could give her money for insurance.