McGonagall through the ages (Picture: Warner Bros)

Prepare to be shocked, Potter fans.

The upcoming Fantastic Beasts film, The Crimes of Grindelwald, has risked upsetting hardened fans of the Wizarding World with a continuity error before it’s even been officially released.

That’s all because of its proposed introduction of a young Professor McGonagall, who in the original Potter series served as the Head of Gryffindor House and as a key ally of the titular wizard.

But McGonagall’s imminent arrival in the Fantastic Beasts film franchise has only gone and broken canon as, according to Potter lore, McGonagall hadn’t even been born at the time that The Crimes of Grindelwald is set in 1927.

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As superfans will tell you, McGonagall is widely considered by fans to have actually been born in October 1935.

Oh dear…

This utter destruction of the delicate continuity from the Fantastic Beasts series to the Harry Potter books could set a dangerous precedent for the remaining films in the franchise, as who knows how much more tinkering the producers might do to the fictional universe’s set of rules.

FILE PHOTO: Writer J.K. Rowling poses as she arrives for the European premiere of the film "Fantastic Beasts and Where to Find Them" at Cineworld Imax, Leicester Square in London, Britain November 15, 2016. REUTERS/Neil Hall/File Photo
Which other characters might Rowling prematurely bring into the wizarding realm? (Picture: Reuters)

The news of McGonagall’s surprising presence in the new film was first alerted after reports over the weekend strongly linked Irish actress Fiona Glascott with the role of the witch, who is expected to be in her late 20s or early 30s in The Crimes of Grindelwald.

Glascott will be the second actress to play the character, following on from acting royalty Dame Maggie Smith’s turn as McGonagall in the original Harry Potter film series.

But will Glascott’s McGonagall go down well with fans, seeing as her character isn’t even meant to have been born by the time of the new film? We’ll have to wait and see…

The Crimes of Grindelwald is set to be released on November 16.

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