You won't find a better young actor than Jaeden Lieberher. I ended up having one of the best times with him, really. Going to work with him every day was a treat.

I feel for those 19-year-olds who get thrust into the limelight that young.

Film is very much about capturing the essence of things - if you feel it, and you've got the right person shooting it, it'll come across. Theater's a different animal; it's physically different and requires a different discipline. In the theater, you're mining the same material, constantly honing the same thing, executing it and keeping it alive and fresh.

You go back to those films of the '40s and '50s and hear the dialogue, the way the people played off each other, the wordplay. I think we've really lost that in movies.

When you're doing those operation scenes, you not only have to be on top of the dialogue and the rhythm of the dialogue and what's happening dramatically, but you've got to technically get the rhythm right, so that everything is fitting with the dialogue at the right time. And you're performing the operation to the audience that's watching it. Thackery has to present it, as well. In some ways, that's the most challenging.

I had to ride a horse once. In 'King Arthur.' I said I could ride, but I had to call for lessons on the day the deal was signed. I started out on this little chunky thing and slowly moved up. It was months of work.

The medical operations are so challenging because they're so technical, as well. I assumed before we started that we would do the classic thing, when it comes to the operations, that we would do all of these inserts with real doctors.