When James Corden first stood in front of an audience, he had a one-line part in the 1996 musical Martin Guerre. Little did that 18-year-old realize how important music was to become in his career. While he would go on to impressive work on stage in One Man, Two Guvnors, which would bring him a Tony Award for Best Actor, on television with Fat Friends and Gavin and Stacey, and in the film with Into the Woods, it would be as a late-night talk show host that would leave his biggest mark. “Carpool Karaoke” has brought such superstars as Paul McCartney, Adele, Stevie Wonder, Mariah Carey, and Barbra Streisand to banter with him in the now famous automotive musical interludes. Those segments have become Internet sensations. Now the 42-year-old is duetting with the likes of Meryl Streep, Nicole Kidman, and Kerry Washington in Ryan Murphy’s adaptation of the Broadway musical The Prom.

Like Barry in the film, you never went to your high school prom either.

My reasons were much different for not going to the prom. In Britain, it is just not a thing that we have. It might be starting to creep through is what I am starting to realize recently. When I was in school, there was no such thing and I am very grateful. I cannot imagine anything worse than being in school and all the talk is about who you are going to prom with. Are you going to ask someone? For me, that would have resulted in a litany of rejection. I am very pleased to not have had such a moment in my life.

You have had a very eclectic professional history but I can only fathom that one of the things on your creative bucket list, was to lie in a hotel room with Meryl Streep, getting a facial, and talking about your personal past. Congratulations on finally getting that moment.

Thank you (laugh). That scene is glorious. I will never forget when I read it. I had already had a few conversations with Ryan (Murphy) before that scene had even been written. I have to credit him in every single way in how he guided me through every beat of it really. I had so many questions and thoughts and even occasional reservations about doing such a thing. He just held my hand through all of it. I am so proud of those scenes and moments. I am.

The original intention for the big opening number was to close down parts of Broadway in New York but the city wouldn’t give permission. Instead, Ryan had them build a fake theater district in downtown Los Angeles. How was it to shoot that production number?

It was astonishing. It was actually one of the first things we shot. I have not spent much of my career on huge massive sets. I got down there and I cannot stress enough, it was an empty parking lot with massive storage containers and in between, a Broadway street. A block of Broadway. I couldn’t believe what I was seeing. I was walking around with my mouth agape. Then Nicole and Meryl walked on set and they were like, “Oh my God, I have never seen a set design like this.” Well, if the two of them were saying that and they have been on some of the biggest movie sets in the past thirty years, then I am doubly blown away by all this.

One of the concepts in the film is the delicate balance between a healthy ego and narcissism. What kind of relationship do you have in believing in yourself?

Well, that really depends on what day you find me in, as it does for all of us. There is not a performer on planet Earth that doesn’t have some element of ego, somehow ever small and buried penchant for narcissism. I have days where I think, what am I doing? You are terrible. Who are you trying to kid? You should just pack up and go home. Then I have other days when I think there are so many other things I want to do. That is all performers. I don’t trust any performer who is completely self-assured in their most private moments. You need vulnerability to be able to go to places you need to in films and stories.