Hugh Jackman used to "wince" over the Wolverine movies' family-appropriate ratings.
Hugh Jackman and James Mangold
The Australian actor and director James Mangold pushed for the final film in the Marvel series, 'Logan', to be given an R rating and it has been a relief for him to be able to portray the character's dark side free from restrictions.
He said: "It seems to me that Wolverine may be one of the darkest, most complex characters in the comic-book universe.
"Every time for the last 17 years I've seen PG-13, a little part of me has winced going, 'Wolverine would never be in a PG-13 movie'.
"All Jim and I were apprehensive about was taking off the seatbelt, taking off any kind of restriction and just diving into this character."
But the 48-year-old star insists the movie hasn't been given such a high rating because of violent content.
He told SFX magazine: "It's not R rated because of the violence, although there is R-rated violence in it.
"That rating is about the subject matter, the way the characters are treated as well as the way the violence is depicted.
"I think this is far more realistic than anything we've done before in the 'X-Men' franchise and maybe many other comic-book movies, far more human."
Director James previously admitted the R-rating allowed him to have more "freedom" when making the movie as he didn't have to worry about appealing to a broader audience.
He explained: "I knew that if Hugh and I could get an R, then we'll have the freedom to make an adult film.
"Because the second the marketing arm of a studio realises it cannot market to children, five or six creative things happen. The scenes can go deeper, and can be written for adults. Not just language, not just [violence], as you're saying, but the themes can be more interesting, the words you're using can be more complicated. The ideas can be more complicated."
He said, too, that the movie's R rating means there is less pressure to fill 'Logan' with the sort of gimmicks that can create merchandising revenue.
He added: "Also, the film comes under no pressure to be a platform for the sale of toys. Because there's going to be no kids to see it."
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