Scholastic has yet release its initial sales figures for Harry Potter and the Cursed Child: Parts 1 and 2, which became available to the public at precisely 12:01 a.m. on July 31, but initial reports indicate that the book has hit its very high performance expectations. Critical reaction to the book, however, is lukewarm.

After months of preparation and a 4.5 million-copy first printing in North America, Scholastic released Harry Potter and the Cursed Child: Parts 1 and 2 on Sunday. The title is the script version of a new Harry Potter play written by Jack Thorne (and based on an original story by J.K. Rowling, Thorne, and John Tiffany), and became available following the play's official premiere in London's West End.

Booksellers rang in the occasion with a raft of midnight release parties. Susan Tunis event coordinator at San Francisco's Bookshop West Portal, said her store's Potter soiree resulted in a sold-out run on Cursed Child, despite the fact that her staff had ordered a "generous number" of copies. "In the end," she said, "it was one of the most successful days in the store's 10-year history, by any metric."

New York City's Strand Bookstore also had a Cursed Child midnight party, with the event being one of the largest Potter happenings in New York City. AM New York reported that the store sold almost all of its 1,000 pre-ordered copies of the title. Barnes & Noble Union Square also threw a major party to ring in the book's release (and move copies), while New York City's oldest children's bookstore, Books of Wonder, had three live owls on hand, among other things, for its evening bash.

Reporting in the New York Times about some of the midnight release parties around the country, Ashley Ross noted that "so-called Potterheads swarmed bookstores Saturday night... as if they had found the secret winged key that not only let them back into their childhoods but also opened the door to another generation."

Despite the fact that Potter fans turned out in droves, yet again, to get a copy of the latest book extending Rowling's brand—the play picks up where the last Potter book, Deathly Hallows, leaves off—not all critics were bowled over by Cursed Child.

While Michiko Kakutani raved about the book in the New York Times, she said that "even though it lacks the play’s much-talked-about special effects, it turns out to be a compelling, stay-up-all-night read," others were less enthusiastic.

Sara Keating, reviewing the book in the Irish Times, noted that it's not actually written by Rowling, and this fact shows. Noting that the book lacks her "depth of magical and fantastical description," she said many fans will ultimately "be disappointed with this offering."

The PW review of the book noted that "reading this play—more than 300 pages of dialogue and a few scant instructions for the actors—is, of course, an entirely different experience" than reading one of the official Potter books.

Mashable highlighted the fact that a number of Potter of fans are trying to distance Cursed Child from the official Potter series, pointing to disgruntled reactions from readers who are insisting that, for them, Potter's story ended with Deathly Hallows.

In addition to Scholastic's hardcover edition of Cursed Child, Pottermore has released the e-book edition of the title. It went on sale, globally, following the play's official premiere in London, just after midnight British Standard Time. In a press release from Pottermore, the company noted that the e-book marks its "first front-list title since the company’s launch in 2012."

NOTE: This story was been updated from its original version to reflect newly published reviews of Harry Potter and the Cursed Child: Parts 1 and 2.