JK Rowling asks fans to keep Harry Potter play plot a secret

Previews of the production began on June 7 at the Palace Theatre in London's West End, before it officially opens on June 30, reported Female First.

The 50-year-old shared a video and wrote, "Potter fans have always had each other's backs. Today I'm asking you to keep the secrets of Cursed Child."

"You've been amazing for years at keeping Harry Potter secrets so you didn't spoil the books for readers who came after you," Rowling said in the video message.