After James Cameron cast Leonardo DiCaprio as Jack in "Titanic," the young actor approached Cameron and wanted to make some changes to the script. Specifically, he thought his character should have "some affliction," which would allow him to really get stuck into the role. Cameron's response was characteristically curt: "You gotta learn how to hold the center and not have all that stuff, this isn't 'Richard III.' When you can do what Jimmy Stewart did or Gregory Peck did, they just f******...