The Books of the Moment is The Cursed Child by J.K. Rowling, John Tiffany & Jack Thorne.
Ok! First of all, this book is amazing. It’s important to note that while it is a bundle of pages with words on it, it’s a SCRIPT, not a book. 2nd, it’s not 100% written by J.K. and you can pick up on that with some of the dialog. If you can accept those caveats you are in for an amazing continuation of the legend of Harry Potter.
Best ‘thing’ I’ve read ALL summer! Go get this book, your wand and some chocolate frogs and let the magic wash over you! Welcome back to the world Harry & crew, you were missed!