The Black Widowers series consists of six books by Isaac Asimov, each a collection of twelve Black Widowers mystery stories.
While most of the stories have appeared in a variety of magazines, Asimov purposely includes never-before-published stories in each collection. In these stories, a group of men meet each month at a dining club where they meet for dinner. A different Widower hosts every month, and it is the host's privilege to invite a guest to dinner. The guest invariably presents the Widowers with a puzzle to solve. The guest may do this intentionally (coming to dinner in the hopes of being helped) or unintentionally, as in the case of "Nothing like Murder", where a visiting Soviet scientist is the guest and insists that he overheard young people casually discussing their plans for murder. The mystery in this particular story was to find out what the two young people had actually discussed. During the course of a mystery, each Widower asks questions and provides possible solutions to the mystery. Some solutions may be shot down by the guest, and some may not be strong enough solutions to work. Invariably, the Widowers' waiter Henry will solve the mystery, typically by thinking of a simple solution that no one else has realized.