What Could Have Been: During the period of Development Hell on the project, Fox was close to cancelling the project and John Lasseter of Pixar offered Joyce the opportunity to make Leaf Men at Pixar. Fox ended up changing their minds and the project stayed at Blue Sky. Chris Wedge stated that while Joyce's book was great, it felt rather blase for a good Hollywood blockbuster, and the Leafmen were changed into samurai-like warriors. The script went through around five rewrites before they arrived at the script that was ready to be animated in 2009.
Working Title: Leafmen, which is closer to the book the film is based on.