Actor Johnny Depp gave Harry Potter fans a look at his coming portrayal of the pale and disheveled villain Grindelwald, delivering a monologue in character to a cheering audience at San Diego Comic-Con on Saturday.

Depp surprised the crowd of science fiction and pop culture fans by stepping out of the darkness with blonde hair and in full costume, drawing applause from 6,500 fans in a cavernous convention hall.

"The great gift of your applause is not for me, but for yourselves," Depp said in his character's English accent as he waved a magic wand over the crowd.

Depp's appearance followed a panel discussion with Eddie Redmayne, Jude Law and other stars of upcoming movie "Fantastic Beasts: The Crimes of Grindelwald," the second movie in a five-part spinoff of the beloved Harry Potter films.

In his on-stage speech, Depp as Grindelwald explained the character's view of Muggles, the ordinary humans without magical powers.

"I do not hate them," he said. "I say the Muggles are not lesser, not worthless, but of other value. Magic blooms only in rare souls."

"The moment has come to rise up and take our rightful place in the world," he added.

Depp did not participate in the panel discussion and did not take questions following his appearance.

"Fantastic Beasts: The Crimes of Grindelwald," written by Harry Potter author J.K. Rowling, is scheduled to debut in theaters in November.

The movie from AT&T Inc's T.N Warner Bros. studio stars Redmayne as "magizoologist" Newt Scamander and Law as a young Dumbledore, the headmaster of the Hogwarts boarding school where Harry Potter and his friends learned to become wizards.

Rowling has said she thinks of the younger Dumbledore as a gay man who fell in love with Gellert Grindelwald, who later turned out to be evil and violent.

Law said the new movie may be the darkest look into the world created by Rowling.

"The wizards within the wizarding world are suddenly asked what side they are on, what side they choose to join," he said. "Everything is at stake."

(Reporting by Lisa Richwine Editing by James Dalgleish) ((lisa.richwine@thomsonreuters.com; Follow me on Twitter @LARichwine; 1 213 955 6776; Reuters Messaging: lisa.richwine.thomsonreuters.com@reuters.net))