[Photo by: Warner Bros.]

Last week, the cast of Harry Potter And The Cursed Child got a surprise visit from series' author J.K. Rowling just a few days before their opening night on Broadway. Watch below as the novelist drops in on the shocked actors!

Read more: A rare 'Harry Potter' book has been… stolen?

Cursed Child, Rowling's “eighth story” in the popular Harry Potter saga, is a two-part stage play that first premiered on London's West End back in 2016. Starting this month, Broadway patrons will be able to catch the Harry Potter story on the Great White Way at New York City's Lyric Theatre.

And the play's actors—Jamie Parker (Harry Potter), Noma Dumezweni (Hermione Granger), Paul Thornley (Ron Weasley) and more—got a pleasant bolt from the blue when Harry Potter's main writer and guiding force stopped in for an unannounced visit recently, as reported by Bustle.

“I know this is really, really embarrassing, but I know you don’t mind,” Cursed Child director John Tiffany says to the cast in the clip, just before unveiling Rowling as a special guest. “I've got a friend in town, and she's a big Harry Potter fan, and I said I'd introduce her to you.” A big fan, huh?

Watch the surprise below:

Watch more: Nikki Misery's miserable makeover