Disneyland may be The Happiest Place on Earth but "Tron 3" is not getting a happy ending. It's not even getting a happy beginning, since it was killed before it got to live. But what destroyed, or at least tabled, "Tron 3" -- a crowded Disney movie slate; lack of real interest in another "Tron" movie, despite early buzz (and an angry fan petition, see below); or the disappointing box office for Disney's "Tomorrowland"?

Back in April, The Hollywood Reporter said the sequel to "Tron: Legacy" was a go, with Olivia Wilde and Garrett Hedlund scheduled to pick up their roles. However, THR returned late on Friday, May 29 with a never-mind report, saying Disney had chosen not to move forward with the sequel. It was never official to begin with, but THR said prep had started on the third film, with production possibly beginning this fall in Vancouver with Joseph Kosinski returning to direct.

But forget all that. After the "Tron 3" is dead news broke, Variety quoted a Disney executive, who put the blame on a crowded movie schedule:

We had never greenlit the movie, but it was in development for some time. Things in the queue got ahead of it and we have such a big slate out in front of it, we started to think, 'Where does it go?' And it's a pretty big investment to make if you are not even sure when you are going to release it."

Not everyone is convinced this is just about a crowded movie slate. THR noted that, while Disney has had success with live-action versions of fairy tales like "Cinderella" and "Maleficent," it stumbled a bit with "Tomorrowland," which cost about $180 million and underperformed with a $33 million U.S. debut. They just put that information out there without blame, but some readers picked up the scent and think there is a connection between those disappointing numbers and Disney not moving forward with another big budget movie. According to Variety, the plan was for "Tron 3" to cost roughly as much as the second, which had a $170 million budget. A source told the site the movie "could resurface at some point but it's not going to get the go button right now."

Several fans are upset at the "Tron 3" news, and a Change.org petition was launched asking Disney to revive the movie. As fan Lucas Lowman wrote:

Tron: Legacy grossed over 400 million dollars and helped more fully realize the world created in the original Tron. It's a shame that Disney has elected not to move forward with a third Tron film as the universe is ripe to be explored. Sign this petition so that we may show Disney that The Grid is too great to never be shown again and to prove that Flynn lives."

So far, the petition has more than 12,000 signatures. Do you hope "Tron 3" does arrive eventually, or is this no great loss to you?

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