Without getting into spoilers, the movie we ended up with is very much an origin story for the Turtles as they emerge from the sewers and try to become heroes to the people of New York City. That’s where the crime villain plot comes into play, with Ice Cube’s Superfly serving as the main villain. It would have been tough to get there in a natural way if they were also trying to do the whole “now the Turtles are in high school” fish out of water bit. The way in which Rowe realized things were broken sounds, to put it lightly, very stressful.
“I think Seth and I first broached that with each other maybe in a text message or something, but it was like, ‘Okay, I don’t want to say this out loud, I’m just going to say this out loud. It’s kind of scary, but I think the movie is fundamentally broken.’ And everything that we’ve assumed it has to be needs to change completely.’ When he voiced that, I felt like terror because he was 100% correct. It was like, ‘Yes, that’s absolutely correct. We have to completely change everything. We don’t have time to completely change everything. Let’s figure out how to completely change everything.’ I feel like that was only last summer.”
Generally speaking, an animated movie takes a long time to make. So the idea that Rogen and Rowe only realized a little more than a year ago that they needed to restructure the entire thing is hard to truly process. In some ways, it hardly even seems possible. But they knew what they needed to do as storytellers, and Paramount Pictures apparently backed that decision, regardless of how disruptive it was.
Source From: www.slashfilm.com