The 29-year-old actor will play Captain America in the Marvel blockbuster - which draws together a number of superheroes, including Thor, The Hulk and Iron Man - but insists he doesn’t know what will happen in the film.

He said: “I don’t know anything. I don’t even know what they’re thinking plot-wise. It’s strange. I’m in a movie and I have no idea what it’s about. It’s a blind challenge I’m facing.”

Chris – who previously played superhero The Human Torch in ‘Fantastic Four’ – will first play Captain America in the forthcoming movie ‘Captain America: The First Avenger’ and admitted he was both excited and terrified the first time he donned his costume.

He told Empire magazine: “I’m trying to approach this as if it wasn’t a superhero movie. It’s just about a guy who gets this amazing gift.

“But the first time I put on the costume, it was a real mix of excitement and terror, ‘What have I gotten myself into?’ But it’s started to feel more like home. A lot of responsibility comes with this costume, I hope I’m doing it justice. Man, I could be wearing this for ten years.”