'Avengers: Infinity War' star Chris Evans reveals 'this could be it' for Marvel contract for him and co-stars

The movie star also opens up about his Broadway debut in "Lobby Hero."

"A lot of our contracts are through. Myself, [Robert] Downey Jr., [Chris] Hemsworth, we all started roughly at the same time, and I think we all through 'Avengers 4' kind of wrap it up," Evans said on "Good Morning America" today. "I don't know what's next -- but by 2019, that's it."

Evans, 36, said he was able to read the top-secret script in its entirety. "They let me read it, but you've got to get fussy. The level of secrecy has only increased over the years, and they're so worried about leaks, so you really have to kind of put your foot down and say, 'Give it to me.'"

"You all get together and act like little kids in school and especially on this movie, there's so many people coming together. I mean, it really is hard to remember that we're professionals and we're here to do a job," he said, laughing.

"It's everything I wanted it to be. I was looking for a different approach to what I do and I grew up doing plays. I was a real theater dork and it's been fun," he said.

"It's a little terrifying, but it's finally settled into a place that feels comfortable and the cast is great. The play is actually really good. I don't normally say that lightly about things I'm working on, and it's something I'm proud of and I'm having a great time."

The Boston native said he is enjoying life in New York and Captain America fans will have to stay tuned to see what happens with his Marvel contract.

"Avengers: Infinity War" hits theaters April 27.

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