Law joins the cast as "young Dumbledore," or, as his castmates like to call him, "hot and sexy Dumbledore" and "delicious Dumbledore." The 45-year-old actor, however, described the younger version of the Hogwarts headmaster as "mischievous" and "manipulative."
"He's a little younger than he was in the Harry Potter series. He's still mischievous, and he can be manipulative," Law said of his character. "He has a great friendship with Newt. Newt was a student of his, a student that he championed."
"There's a little bit of a past there, which I think is already known," he said, turning to Redmayne for confirmation. "Right? That Newt was asked to leave Hogwarts and Dumbledore tried to stand up for him. Newt has this capacity to always act in the right way for the right reasons, and it's something that Dumbledore relies on in this situation, because Dumbledore cannot get involved in the confrontation that is at the heart of this film. So Newt is sort of his conduit."
Jude Law Reveals How J.K. Rowling Helped Him Prepare to Play Dumbledore! (Exclusive)
TheFantastic Beasts and Where to Find Them follow-up transports the story to Paris, where Dumbledore (Law) tasks Newt Scamander (Redmayne) with stopping the eponymous villain, Grindelwald (Johnny Depp).
Devoted Harry Potter fans know the reason why Dumbledore "cannot get involved in the confrontation" that will happen in the second film. J.K. Rowling revealed shortly after the original book series ended that Dumbledore was gay and had a very intense and romantic relationship with Grindelwald when they were young men. While fans don't get to see any real scenes with Law and Depp in the new trailer that was released during the film's Hall H panel on Saturday, they did see a snippet of Dumbledore looking at the Mirror of Erised and seeing his deepest desire: Grindelwald.
Depp surprised Comic-Con fans during the panel when he showed up in character. The 55-year-old movie star appeared dressed as the villainous Grindelwald, rocking a short, platinum-blond cut and period-era coat while waving a magic wand at the throng of cheering fans inside the massive Hall H before they screened the trailer.
The cast told ET they knew Depp was coming. "They flipped their lids," Waterston explained, with Law adding, "They flipped their lids, and then, when he started speaking, it went silent. You could hear a pin drop. It was amazing."
The cast has had an incredible time together and is ready to show the world a "darker" film.
"It is darker," Redmayne explained. "Although, I felt like when the Harry Potter series came out, each time there was a new book or a new film, all of the reviews would be like, 'It's much darker than the last one.' But I was always like, 'How dark can it get?' But this one compared to the first, [is darker]."
For more on the fantasy film, watch below.
Fantastic Beasts: The Crimes of Grindelwald hits theaters on Nov. 16.