One thing that has not changed during the director switch-up is the original Good Dinosaur story premise co-conceived by Peterson and Enrico Casarosa (director of the Pixar animated short "La Luna"): that, in this film's alternative reality, there was never a huge extinction event (like an asteroid hitting Earth) that wiped out the dinosaurs millions of years ago; and thus, dinos have always co-existed with modern humans in the movie (so no Jurassic Park-style battles for alpha dominance).
Good Dinosaur is essentially a buddy comedy about a young Apatosaurus named Arlo and his newfound "pet", the wild human boy that he names Spot. Speaking with the LA Times, Sohn explained that the film's narrative core has remained the same under his supervision; namely,"It's always been about this young dinosaur growing up." As such, the movie's world-building process is where Sohn has worked harder to leave his thumbprint on the project.
"When Bob was taken off, I was supporting the film as best I could. It felt like, this child, this film still needs to be raised. It was just about how to take care of the thing at that time. ... Trying to keep the original vision of this film intact and trying to plus it as well."
Two specific changes that Sohn implemented on Good Dinosaur (following Peterson's departure as director) include how the dinosaurs are presented - they are no longer modeled after Amish farmers as Peterson had planned - as well as the role played by nature, which Sohn says has "become a character" in his rendition of the story. Voice cast member John Lithgow's comment about the project having been "completely reimagined" is easier to understand now, given this new insight on how the movie's universe has been revised.
Check out fresh concept art from The Good Dinosaur, below (click for the full-size version):
Pixar's last original animated feature, Brave, also endured a very public passing of the torch from one director to another during its production. And while the Oscar-winning film was ultimately a success both critically and financially, Brave has also been (fairly) criticized for feeling a bit like a mix of elements from two different directors' visions. (That the final result with Brave was nonetheless arguably a very good to excellent animated adventure is a testament to Pixar's commitment to quality storytelling.)
Good Dinosaur's director change-up seems more amicable than that on Brave; Peterson's still working for Pixar (currently lending a hand on Inside Out and Finding Dory), while it sounds as though Sohn is invested in building on the foundation that his predecessor has already laid down... in his own style, is all. Ratatouille's director of photography Sharon Calahan and production designer Harley Jessup are helping Sohn on Good Dinosaur (according to the LA Times article), which is also encouraging news.
The Good Dinosaur opens in U.S. theaters on November 25th, 2015.
Source: LA Times