The star took on the character in 2009's X-Men Origins: Wolverine, but had wait several years to make the spin-off, which became a big box office hit. The 40-year-old is currently working on the sequel to the film, and he hopes he can handle the pressure a little differently this time.

"I felt like I was on some schooner in the middle of a white squall the whole time," he tells GQ magazine. "It just never stopped. When it finally ended, I had a little bit of a nervous breakdown. I literally had the shakes.

"I went to go see a doctor because I felt like I was suffering from a neurological problem or something. And every doctor I saw said, 'You have anxiety'."

"I say this with the caveat that I completely recognise the ridiculously fortunate position that I am in," he adds, "but the attention is hard on your nervous system - that might be why I live out in the woods. And I was banging the loudest drum for Deadpool. I wasn't just trying to open it; I was trying to make a cultural phenomenon."

Ryan originally wanted to make the Deadpool film before X-Men Origins: Wolverine, but was told studio executives would never put the movie into development.

"It's like when your husband or wife is out there doing interviews and constantly batting their eyes about some other actor or actress," he says.

He even wrote to studio bosses at Fox right before he took the lead in flop movie Green Lantern, threatening to grab the role for a rival if they didn't agree to make Deadpool: "I'm at the altar, about to say 'I do' to somebody else, but tell me you want to spend the rest of your life with me, because I want to spend the rest of my life with you'," he shakes his head, "and they said, 'Unfortunately, we can't green-light that movie, and I don't think it's gonna ever get green-lit'. So I was like, 'OK, I'm gonna go move on with my life, then, I guess'."

But he got his revenge when Deadpool was released and the "Thursday midnight numbers" indicated it was going to be a box office smash in the U.S.

"I just went, 'Whoa!'" he recalls. "We made our production budget back on Friday. There's a certain vindication that comes with that, especially because the studio - granted, under different regimes - for years just kept telling us to go f**k ourselves sterile."