 Unlike Heinlein's lunar society, Varley's convict society on Charon maintains its criminal ways and is similar to the mafia or the yakuza.His "Thunder and Lightning" series plays on his connection with Heinlein by deriving its main characters' names from many of Heinlein's characters, including Jubal, Manuel Garcia, Kelly, Podkayne, Cassie and Polly, and by frequently dropping titles of Heinlein's novels in the dialogue.Early in his career Varley wrote a trilogy of novels set in a sentient hollow world reminiscent in structure to a very large Stanford torus space habitat, but with a distinctly different personality.