With Fantastic Beasts: The Secrets of Dumbledore being set a decade after the second film, in 1939, it means that the third movie could include Tom Riddle, aka Voldemort. The temporal leap between The Crimes of Grindelwald and The Secrets of Dumbledore is quite jarring.
Presumably, Grindelwald has spent the past ten years amassing a following to his cause and Dumbledore has been plotting the best way to defeat Grindelwald. As for Newt, the future is murky especially since the third installment's
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