The character of Caleb has a very unorthodox style of running in the movie, particularly near the start. This was a choice made by actor Ansel Elgort who stated that, "Shailene Woodley and Theo James are superheroes. Caleb is not. Caleb represents the intellectual side, the guy who isn't physical. And I wanted to make sure that was on screen. I wanted to make sure that made sense."
According to Miles Teller, in 90% of his scenes he is bleeding from Tris (Shailene Woodley ) beating him up.
Unlike the first film, Insurgent is a very loose adaptation of Veronica Roth's novel, which contains a vastly different plot.
After cutting her hair for the role of Hazel Grace Lancaster for The Fault in Our Stars (2014), Shailene Woodley decided she did not want to wear a wig for Insurgent. In the book, Tris does cut her hair but not as short as seen in the movie.