I was a Hollywood musical fan as a kid, and I know how rare it is for someone who originates the Broadway role to get to then do it on screen.

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.

I think Frankie Valli did everything right. He kept singing. And you also have to remember, he was confined to a certain society, which was this sort of like - the wrong side of the law kind of society of Italian guys from the streets of Belleville, New Jersey. So he found his way.

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.

I think one of the ways that these young singers got started is that they would end up in clubs. And a lot of them were mafia owned. And so there was almost an unspoken kind of mafia sponsorship, which is just a very interesting part of that area's music history.

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."

I approach the singing kind of like with dialect thoughts in my mind. I have to sound like this on certain things to give that Frankie Valli flavor.