I've learned to keep my work on the stage or on the screen.

I know, for me, you know, my generation - I never would have known anything about Robert Preston's performance in 'The Music Man' if there hadn't been a film where he played the part. I just heard how great he was on Broadway way before my time.

I'm kind of happy to know there may be some kid or teenager now who might never have had the chance to see my Broadway performance, but gets a taste for what it might have been like now, because they can see Clint Eastwood's film."

But when you get to know a character so well, you start to have insights that you can't show because you're confined to your script of your hit show.

It was a surprise to me and a happy accident that it was such a skill [natural falsetto] - a latent skill and that there was a way to exploit it. And it was a key to playing great role Frankie Valli in such a huge show.

I think you couldn't do this role or you couldn't be Frankie Valli himself unless you had a natural falsetto. And I had sort of discovered it by accident as a child or a young adult when you realize you have a special skill that you don't really have any use for you, and you just take it out at parties or to amuse your friends or to annoy your girlfriends.

It was great to play for a live audience on a stage.