[Making 'Frozen'] It was much more of an action adventure, and we really wanted to go more musical, with more comedy. I made a commitment to writing the script with the songwriters, where you're going back and forth a lot. So we all had to be on the same page and have the same vision. I was getting excited about Bobby and Kristen's ideas (the husband-and-wife songwriting team of Robert Lopez and Kristen Anderson-Lopez); they were getting excited about my ideas. Really, it's just about creating a very powerful, emotional story, but also having it be something that is a lot of fun and actually quite epic, something big.