An aspiring teen detective stumbles into her first real case, when investigating the mysterious new family in her neighborhood.

The Andorran hooker and single mother Catalina "Cat" Rona is hired to participate in an orgy in Montenegro with other escorts and powerful men and the American Senator William Krebb. Something goes wrong with the politician and all the girls are murdered by the security of the host to avoid witnesses. However Cat escapes and brings a hard-drive with classified information with her. There is a manhunt for Cat and the cruel assassin Helen Bingham is hired to retrieve the HD and kill Cat. Meanwhile the Americans Julian Simms and Anthony Hester decide to open a detective agency to raise money. When they see on the newspaper that Cat is being chased, they decide to seek her out expecting to receive a reward. However, they cross the path of Helen and they end protecting Cat from the killer. When Helen is betrayed by those who had hired her, she decides to help Anthony, Julian and Cat to retrieve the HD and their freedom.

Former high school English teacher and famed mystery writer Jessica Fletcher has a gift for solving mysteries. You see, it seems murder follows her around, whether it be to the houses of her seemingly endless number of friends, nieces, and nephews or right in her hometown of Cabot Cove, Maine. Jessica is sometimes assisted by her friend Dr. Seth Hazlitt or the local sheriff, Amos Tupper (later Sheriff Metzger). Sometimes, later in the series, Jessica would only narrate the episode, which would be a dramatization of one of her novels. In later seasons, Jessica moved to New York City to be closer to her publisher and also closer to crime.

In a small Massachusetts town, two bumbling criminals mistakenly kidnap a maid, thinking her to be the wife of a prominent businessman. D.C., short for Darn Cat, is an alley cat who, while looking for his nightly snack, stumbles upon the kidnap victim, bound and gagged in a shed. The kidnap victim scratches a plea for help on the back of her wristwatch and puts it around the cat's neck. Patti finds the watch and links it to the missing maid. Playing amateur detective, she enlists the aid of an FBI agent, Zeke, who has been assigned to the case. Patti and Zeke follow D.C. through tight openings to track down the captive.