De Niro felt that the time was right for a movie about a comic. "I thought it was such a great idea to do a comedian," he says. "That has never really been done before. Maybe The Entertainer [the 1960 drama starring Laurence Olivier]. But not like this. And a comedian can do things that are more outrageous, even if it's not my personal taste. That was my attraction."

Robert De Niro as Jackie Burke in The ComedianRobert De Niro as Jackie Burke in The Comedian

He also relished the challenge of learning to actually do a stand-up comedy routine. "It's hard," he admits. "You have to have the right material. I worked on this material, but it wasn't like I worked on it for years and had it all there. I don't know how to deal with a heckler. That takes a lot of experience! I did OK, but you just have to get through it. Even though my audience was extras, you can feel like you're dying out there if they don't laugh. You want a reaction."

Of course, De Niro has played a comedian before. In Martin Scorsese's 1982 blackly funny thriller The King of Comedy, he played the now-iconic Rupert Pupkin, an aspiring comic who stalks his idol, a chat show host played by Jerry Lewis. When reminded that Rupert wasn't quite as funny as Jackie is, De Niro is quick to defend the earlier role: "I like the jokes that Rupert Pupkin had! I worked on that for a while. I found it hard, that it wasn't as easy as I thought it would be."

And in The Comedian, De Niro found resonance in the way Jackie is constantly reminded of his earlier, more successful roles. When looking back at the young actor he was in classics like Taxi Driver and The Godfather, De Niro says, "I'm different in certain ways. I don't spend as much time on certain things that I would have concerned myself more about when I was younger, because I don't feel that I need to put that much time and effort in it."

Even so, he admits that this project brought these ideas into his mind. "This is about a guy getting older," he says, "a guy who didn't really make it and got stuck in his character. He's getting older, getting marginalised, as time goes by. I can't not think about that. It's real."

Watch the trailer for The Comedian: