As some Harry Potter fans attempt to figure out if it’s possible for Credence Barebone to actually be Albus Dumbledore’s long-lost brother Aurelius, others are wondering about a different potential Fantastic Beasts: The Crimes of Grindelwald question.
During a flashback to Newt Scamander (Eddie Redmayne) and Leta Lestrange’s (Zoë Kravitz) days at Hogwarts, a young Minerva McGonagall (Fiona Glascott) appears as a professor at the famous school of witchcraft and wizardry. She also makes a cameo in another Hogwarts scene set in 1927, the year in which the majority of the movie takes place.
However, according to Harry Potter canon, McGonagall wasn’t born until 1935, which complicates her appearance within the Crimes of Grindelwald timeline. During a conversation between McGonagall and Professor Umbridge in Harry Potter and the Order of the Phoenix, McGonagall tells Umbridge that, come December, she will have been teaching at Hogwarts for 39 years. Harry’s fifth year at Hogwarts begins in 1995, meaning that McGonagall didn’t start teaching at Hogwarts until 1956.
Pottermore lists McGonagall’s birthday as October 4 and states that she worked at the Ministry of Magic for two years after graduation before returning to Hogwarts as a professor. Since magical children begin attending Hogwarts at the age of 11, this means that McGonagall would have started school in 1947 and was therefore born on October 4, 1935 — eight years after the events of Crimes of Grindelwald.
There also doesn’t seem to be a chance that the McGonagall seen in Crimes of Grindelwald is an older relative of Minerva as the published screenplay lists the character as Professor Minerva McGonagall.
Unless J.K. Rowling has a yet another magical time traveling twist in store for fans, it seems as though McGonagall’s appearance in Crimes of Grindelwald could indeed be a plot hole.