In the book, Iger explains that Disney purchased Lucas' outlines for three new movies when it made a deal to acquire Lucasfilm in 2012 — although that purchase was, in part, made out of a sense of obligation, it's suggested; "[W]e decided we needed to buy them," the chief exec writes of the decision made with studio head Alan Horn, "though we made clear in the purchase agreement that we would not be contractually obligated to adhere to the plot lines he'd laid out."

As it turned out, Disney and Lucasfilm didn't follow Lucas' lead for the new movies, a decision Lucas discovered when Lucasfilm head Kathleen Kennedy and Star Wars: The Force Awakens writers J.J. Abrams and Michael Arndt met to discuss the new trilogy, and specifically the 2015 installment.

"George immediately got upset as they began to describe the plot and it dawned on him that we weren't using one of the stories he submitted during the negotiations," Iger writes. "George knew we weren't contractually bound to anything, but he thought that our buying the story treatments was a tacit promise that we'd follow them, and he was disappointed that his story was being discarded. I'd been so careful since our first conversation not to mislead him in any way, and I didn't think I had now, but I could have handled it better."

Added the CEO: "George felt betrayed, and while this whole process would never have been easy for him, we'd gotten off to an unnecessarily rocky start."

Things didn't improve when Lucas saw the finished movie. Following a private screening, Iger recalls, Lucas "didn't hide his disappointment. 'There's nothing new,' he said. In each of the films in the original trilogy, it was important to him to present new worlds, new stories, new characters, and new technologies. In this one, he said, 'There weren't enough visual or technical leaps forward.' He wasn't wrong, but he also wasn't appreciating the pressure we were under to give ardent fans a film that felt quintessentially Star Wars."

The problem, Iger suggests, is that Lucas didn't fully appreciate what Lucasfilm and Disney were trying to do with the new trilogy, and specifically The Force Awakens. "We'd intentionally created a world that was visually and tonally connected to the earlier films, to not stray too far from what people loved and expected," Iger explains, "and George was criticizing us for the very thing we were trying to do."

In retrospect, Lucas' complaints mirror some of those from the vocal minority of Star Wars fandom upset about the direction the franchise has taken since Disney's purchase. While Iger stays away from agreeing with the criticisms in the book, in promoting its release, he has accepted that Disney's plan of releasing a new Star Wars movie every year might have hurt the property.

"I just think we might've put a little bit too much in the marketplace too fast," he told The New York Times in a profile published over the weekend, while adding, "I think the storytelling capabilities of [Lucasfilm] are endless because of the talent we have at the company, and the talent we have at the company is better than it's ever been, in part because of the influx of people from Fox."

A rep for Lucas told The Hollywood Reporter that the Star Wars creator had no comment on Iger's book.

The Ride of a Lifetime: Lessons Learned From 15 Years as CEO of the Walt Disney Company is available now from Random House.