LONDON — The eighth installment of the Harry Potter series was presented on Tuesday evening at the Palace Theater here. Neither a book nor a film, it was a play, “Harry Potter and the Cursed Child.” But whatever the medium, the Potter saga continued with unabated interest: fans dressed in Hogwarts costumes, curiosity about the fate of long-beloved characters and the allure of magic.

Harry Potter and His 2 Friends Remain True to Themselves

When we last left Harry Potter, in the very last pages of J.K. Rowling’s “Harry Potter and the Deathly Hallows,” he was a middle-aged bureaucrat sending his middle child, Albus Severus, off to Hogwarts for the first time. After the violence and darkness that had marked his younger years in Ms. Rowling’s story, all seemed well.

Now Harry is back — in a play, this time — and all is not well. “Harry Potter and the Cursed Child,” which had its first preview in London on Tuesday, begins with the final scene from “Deathly Hallows” and skitters rapidly forward a few years, sketching out Albus’s feelings of alienation both from Hogwarts and from his famous father.

It is jarring and exciting to be seeing characters who seemed to be put to rest, suspended forever in place and time, suddenly reanimated. At the same time, the three main characters remained true to their younger selves. Ron still provides comic relief, Hermione remains cerebral and slightly bossy and Harry tries as hard as he can but doesn’t quite live up to his own expectations.