Fantastic Beasts and Where to Find Them producer David Hayman explained Johnny Depp's choice to play the wizard of Grindelwald. According to him, quoted by Collider, the creators of the series needed a "real icon" of Hollywood.
"We wanted a cult actor to play this role, as Grindelwald is an iconic character that has a huge impact on the whole story. His ability to take over the minds and hearts of people and make them follow him is a defining factor. That is why we needed someone who can be both charming and original to be a cult and very talented actor, and all these qualities Johnny Depp has. He can be simply irresistible. He created several very famous images on the screen, and often makes very non-trivial creative decisions. This unpredictability is partly what makes him such an extraordinary actor, which is very important for us. In short, he was the perfect choice in this case, "he said.
Note that a significant part of the fans did not like the look of Johnny Depp's character in the movie, as he did not at all correspond to the spirit of the times and resembled some of the other heroes of the actor from other costumed movies.
The Topic of Article: Fantastic Beasts Producer Explains Johnny Depp's Involvement.