Fashion model Maddie Hayes is awakened one morning to discover her volatile Italian chef breaking all the dishes in her kitchen. She discovers that his last pay cheque bounced, and on further investigation, discovers that her business manager has absconded with all of her funds, leaving her effectively bankrupt.
She does have some other assets in the form of companies that she owns, however, so she needs to liquidate these companies in an attempt to pay off her debts. One of the companies is the "City of Angels Detective Agency" (which was its original name before it became "Blue Moon Detective Agency"), run by a wiseguy sleuth named David Addison. Addison attempts to convince Hayes that they can make the agency profitable if she will agree to become his partner. Hayes cannot stand the sight of Addison so things don't look promising.
As luck would have it, they witness a murder in an elegant restaurant, which leads them into a case involving an apparently worthless wristwatch containing clues that point them towards a fortune in diamonds. Needless to say, by the end of the episode, the Blue Moon Detective Agency is born, and Maddie Hayes and David Addison become (from her point of view at any rate) reluctant business partners.