Nick Sagan is the author of the bestselling science fiction novels Idlewild, Edenborn, and Everfree, and the son of astronomer Carl Sagan. Mark Frary is a science and technology writer who has written screenplay adaptations of science fiction, animation episodes, and computer games for studios such as Paramount, Warner Brothers, Universal, and Disney, as well as Tom Cruise and Martin Scorsese's production businesses. Codebreaker: The Hidden History of Communication is his coauthorship. Andy Walker is the cohost and coproducer of the video podcast Lab Rats and the author of Absolute Beginner's Guide to Security, Spam, Spyware, and Viruses.