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The Black Widowers were based on a literary dining club Asimov belonged to known as the Trap Door Spiders. Members of the Widowers were based on real-life Spiders, some of them famous writers in their own right:
* Geoffrey Avalon (based on L. Sprague de Camp)
* Emmanuel Rubin (based on Lester del Rey)
* James Drake (based on Dr. John D. Clark)
* Thomas Trumbull (based on Gilbert Cant)
* Mario Gonzalo (based on Lin Carter)
* Roger Halsted (based on Don Bensen)
The deceased founder of the club, Ralph Ottur, on whom the plot of the story "To the Barest" turned, was based on the real-life founder of the Trap Door Spiders, Fletcher Pratt. The stage magician The Amazing Larri, from the story "The Cross of Lorraine", was based on James Randi. The arrogant science fiction writer Mortimer Stellar, from the story "When No Man Pursueth", was based on Asimov himself.