As part of his biographical research on George Lucas in the early 1980s, Lucas allowed author Dale Pollock to read the plot outlines of a 12-film saga on the condition of signing a confidentiality agreement. Pollock said these sequel trilogy drafts would "involve Luke Skywalker in his 30s and 40s" and that they would be "The three most exciting stories ... They had propulsive action, really interesting new worlds, new characters." Lucas's plans were drastically changed after "The Empire Strikes Back" was released, owing to the stress of producing the first three films as well as pressure from his wife to step back from this kind of filmmaking. By 1981, Lucas had decided to make only one "Star Wars" trilogy.