Oscar Isaac felt "insecure" filming 'Star Wars: The Force Awakens'.
The 36-year-old actor felt he wasn't being very "creative" on the set of the sci-fi blockbuster - which is directed by J.J. Abrams and worried he wasn't "finding enough" depth to his character, Poe Dameron.
He said: "I actually felt the most green and insecure than I had in a long time. I was like, 'What am I doing here?'
"There was a lot of room to shade in the character. Every time I tried to do that, it would slow things down too much. J.J. would be like, 'Get on with it, man!' Just, Louder! Faster! And then I would feel like I was doing that all the time.
"It felt weird and like I was not being creative. I would get nervous I wasn't finding enough or I was missing an opportunity."
However, Oscar insists he isn't feeling anxious about reprising the role again because there is nothing concrete he has to stick to.
Asked if he's anxious about doing more 'Star Wars' movies, he told America's GQ magazine: "No! Because what's so fun about it is...it's all made-up! It's all f***ing made-up, but in a great way. We get to create it as we go."
Oscar - whose full name is Oscar Isaac Hernandez Estrada - was raised in a very religious household but didn't understand why he never felt "the real thing" in the way his father did.
He said: "My dad was a man of extremes. And the way my mom was raised, she followed her husband. So if God spoke to my father one day and said we were not supposed to have a TV in the house, it was suddenly gone.
"The Hernandez home became the site of a kind of ongoing tent revival...
"I was never frightened by it. I was more curious why I wasn't feeling the real thing myself."