Another 250,000 tickets for new stage play Harry Potter And The Cursed Child are set to go on sale next week.
The two-part play officially opens at the Palace Theatre, London, on Saturday.
Following rave reviews, the show's producers have said more tickets will be made available from 11am on August 4.
Every performance will have 300 tickets available, priced at £15 to £20 per part.
The play is a follow-up to author JK Rowling's Harry Potter novels and follows Harry's life 19 years after the events of the final book in the series, The Deathly Hallows.
It lasts more than five hours and is presented in two parts, intended to be seen on the same day - a matinee and evening performance - or on consecutive evenings.
Previews have been held since June, and early reviews have described it as being "out of this world" and "a theatre production of immense wonder".