Void Moon is the ninth novel written by Michael Connelly, and the first to feature Las Vegas thief Cassidy Black. The book was published in 2000. The novel's title "refers to the condition of the Moon between the moment it performed the last major aspect with another planet in its current sign and the moment of stepping into the next sign." At such a time, the Moon is said to be "void of course." The events of the book are mentioned as having been made into a film in the novel Lost Light.