Bill Watterson's Calvin and Hobbes is one of the most famous and popular comic strips of all time. The strip, which follows the richly imaginative adventures of six-year-old Calvin and his trusty tiger, Hobbes, has been a worldwide favorite since its introduction in 1985.

Watterson has made it clear that he isn’t interested in a Calvin and Hobbes adaption, but not all fans share this sentiment. So it’s fair to wonder — if an adaption did happen, what might it look like? And might a darker take on the classic strip be the way to go?

An Adaption Is Unlikely, for Now

Calvin and Hobbes
Andrews McMeel Publishing
20th Century Studios

As the series closes out its fourth decade as one of the most beloved comics on Earth, there is curiosity among many fans about what might be next for the duo. An adaptation doesn’t seem likely, at least during Watterson’s lifetime. As he told Mental Floss in 2013, “I have zero interest in animating Calvin and Hobbes.” Waterson explained — “Because different media have different strengths and needs, and when you make a movie, the movie's needs get served. As a comic strip, Calvin and Hobbes works exactly the way I intended it to. There's no upside for me in adapting it.”

This hasn’t stopped fans from speculating on what an adaptation might look like, though, and one of the more interesting ideas would require that adaptation to have an R rating.

Why an R-Rated Calvin and Hobbes Movie Might Work

Calvin and Hobbes
Andrews McMeel Publishing
20th Century Studios

An R-Rated adaptation of a comic strip aimed primarily at children might sound counterintuitive, but an unexpected take might be the best way to approach a property as iconic as Calvin and Hobbes.

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One way to approach this would be to recontextualize Calvin’s overactive imagination as a sort of genuine disconnect from reality; there already is a theoretical concept that Calvin is suffering from schizophrenia, which is oddly similar to a theory surrounding Winnie the Pooh. There's even a book about this, called Calvin, which could be adapted. This could take the shape of the kind of grim and gritty remake that we’ve seen for everything from Batman to Velma Dinkly. Conversely, a thoughtful, adult-oriented movie exploring Calvin’s optimism and creativity as he navigates growing up might result in a fascinating coming of age story, or a more idiosyncratic look at his relationship with his imagination might have more in common with Eternal Sunshine of the Spotless Mind than, say, Garfield.

Why an R-Rated Calvin and Hobbes Movie Might Not Work

Calvin and Hobbes
Andrews McMeel Publishing
20th Century Studios

These possibilities do raise the question, though: Would something along these lines work as a Calvin and Hobbes adaptation? How much can the original characters, context, and tone of the comic strip change before they become something else entirely? As adaptations become a more and more common part of Hollywood, fans of the original properties being adapted have often been vocal in their opposition to deviations that they deem too extreme. The fundamental issue in these cases is which traits in these characters are essential, and which can be successfully modified.

In the case of Calvin and Hobbes, creators and audiences would have to decide which category the aspects of the strip that have to be changed for an R-rated adaptation aimed at the adult audience to succeed fit into. Is the innocence of childhood a key ingredient of the strip, or can it be sacrificed for a take that comes at the characters from a darker angle?

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If it’s the former, and an R-rated adaption of Calvin and Hobbes would be doomed to failure as either an adaption or else on its own terms. In such a case, a better approach might be to pick up the themes or ideas from Calvin and Hobbes that would resonate in a R-rated film and incorporate them into a new property. A man struggling to get a handle on his chaotic imaginary friend could easily work as the foundation for an R-rated film, and, in fact, already has.

Did an R-Rated Calvin and Hobbes Movie Already Work?

Fight Club cast with Brad Pitt shirtless and bloody
20th Century Studios

David Fincher’s 1999 film Fight Club features a man led slowly but surely into madness and destruction by his id-driven imaginary friend, and plays, in many ways, like an R-rated take on the premise and structure of Calvin and Hobbes. The theory that Edward Norton’s unnamed protagonist is secretly a grown up version of Calvin, with Hobbes taking shape as Brad Pitt’s anarchic Tyler Durden, a projection of the protagonist’s most unrestrained impulses, manages to provide an interesting lens through which to consider both Fight Club and Calvin and Hobbes.

Galvin P. Chow first articulated this theory in a now deleted post on Metaphilm (quoted here), writing that a grown up Calvin is forced to repress his imaginary childhood companion. As the theory goes, “while he is busy growing up, deciding what ‘dinette set defines him as a person,’ Hobbes is also maturing in the recesses of his mind, waiting to be unleashed at an appropriate time.”

So all in all, an R-rated Calvin and Hobbes movie could work — it just might not look the way you’d expect.