When he's not saving the Earth alongside Batman, Superman, Wonder Woman, Aquaman and Cyborg, "Justice League" star Ezra Miller apparently spends his time poring over "Harry Potter" minutiae. Oh, and appearing in "Fantastic Beasts and Where to Find Them," of course.

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In a new promo for the upcoming film, the 23-year-old actors proves just how obsessive he is about J.K. Rowling's wizarding world by drawing a potential like between the final "Harry Potter" novel and "Fantastic Beasts."

"As we all know, in 'Harry Potter and the Deathly Hallows,' Voldemort goes into Dumbledore's tomb, rudely, to retrieve the Elder Wand," Miller says. "Dumbledore won that wand in a famous duel with the most dangerous dark wizard prior to Voldemort. If you don't know this, I'm upset with you. He was Gellert Grindelwald. It's considered one of the most significant turning points in magical history. Now think about it with me: 'Fantastic Beasts' takes place in 1926, which was around when Grindelwald was beginning his attacks across Europe, which might be connected -- might not be connected, but might be connected to Grindelwald's rise to power."

Got that? Good.

"If you are freaking out as hard as I am right now," Miller continues, "thank you, because it's good to not be alone."

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Directed by "Harry Potter" veteran David Yates from a screenplay by Rowling herself, "Fantastic Beasts" follows preeminent magizoologist Newt Scamander (Eddie Redmayne), who arrives in 1926 New York City, where something mysterious leaves a path of destruction through the streets, threatening to expose the wizarding world to the Second Salemers, a radical group of No-Majs (the American term for Muggles) determined to eradicate them. The situation is further complicated when an unsuspecting No-Maj opens Newt's leather case, releasing his collection of magical specimens into a city already in edge. Now it's up to Newt and his newfound allies to recapture the creatures, even as their mission places them on a collision course with dark forces.

Opening Nov. 18, "Fantastic Beasts and Where to Find Them" also stars Katherine Waterston, Dan Fogler, Alison Sudol, Colin Farrell, Carmen Ejogo, Samantha Morton, Ron Perlman and Jon Voight.

Miller will follow that film next year with director Zack Snyder's "Justice League," which also stars Ben Affleck, Henry Cavill, Gal Gadot, Jason Momoa and Ray Fisher. His "Flash" solo movie is targeted to race into theaters in 2018.