Comedian Stephen Merchant assumed he would be bulking up for his part in X-Men - so was disappointed to discover he simply needed to shave his eyebrows off.
He appears in the upcoming X-Men instalment Logan, and said he had expected to be undergoing a body transformation that would see him become muscly like his co-star Hugh Jackman, who plays Wolverine.
He told The Jonathan Ross Show: "When they said I was going to be in it I thought I was going to be an X-Man.
"I was like 'Do you need me down the gym? What time do you need me there?' They were like, 'We just need you in the barbers at nine.'"
Stephen explained: "I play a giant albino mutant, it's typecasting. I had to shave my head for the role.
"To be honest there aren't a lot of pale-faced, stick thin men in Hollywood so it was either me or they would have done CGI."
The 41-year-old also had to dye his eyelashes white for his role as mutant Caliban, and said: "It was annoying when I was doing it, I kept asking the producers if I could go out into the real world just for fun, just to go into an old people's home with a scythe and just point."
Stephen has previously spoken about having a nude scene cut from West End play The Mentalists, and told Jonathan he is unlikely to appear in the buff on film either.
He said: "I think there's some things you should keep private, I don't think I would because then it's just out there forever and it just sits there in the world."
X Factor judge Nicole Scherzinger, also being interviewed on the programme, agreed: "Actually I was going to do a movie and they asked me to get nude and I was like no, I mean unless it's like for Martin Scorsese or something but no, you don't need to."
The Jonathan Ross Show airs on Saturday on ITV at 9.50pm.