“Harry Potter” fans will know that Dumbledore is a man of many secrets, some of which he even took to his grave at the end of “The Half-Blood Prince.” He held many of these secrets during the timeline of the books and film franchise to ostensibly keep Harry safe, but some of the darkest ones date back to the timeline of the “Fantastic Beasts” series, when Dumbledore was but a young Transfiguration professor, and the greatest threat to the wizarding world was a handsome Hitlerian upstart named Gellert Grindelwald.
Before Grindelwald took a turn for the genocidal, he and Dumbledore were lovers, and together they pursued a shared interest in the Deathly Hallows, magical artifacts that play a central role in the final act of “Harry Potter.” Will the secret of Dumbledore’s relationship with Grindelwald be the titular secret at the core of the third “Fantastic Beasts” film? Or is there yet another layer to this complicated partnership? Only time will tell. Until then, enjoy the first trailer.