In June 2010 Cline sold his first novel, Ready Player One, in a bidding war to the Crown Publishing Group (a division of Random House).[15] The film rights to the novel were sold the following day to Warner Bros. with Cline attached to write the screenplay.[13] Ten months later, with the hardcover release coinciding with the paperback release, Cline revealed on his blog that both the paperback and hardcover editions of Ready Player One contain an elaborately hidden Easter egg. This clue formed the first part of a series of staged video gaming tests, similar to the plot of the novel. Cline also revealed that the competition's grand prize would be a 1981 DeLorean.