(5) Tree Line
Literarily speaking, the Harry Potter series is famous for having a reading level that grows along with its readers. Harry is ten in the first book and seventeen in the last book, and each book in between gets a little more complex and challenging to understand. Just like life, man.
That means you have to be—gulp—forty to really get Harry Potter and the Cursed Child.
Okay, not really. But this story is much more complex and nuanced than any Harry Potter story before it. Although the main storyline centers on fifteen-year-old Albus, the crux (no, not Horcrux) of the story is Harry's abilities, or lack of, as a parent. That can be a challenging subject to grasp, not because of vocabulary level, but because of subject matter. Because those are some seriously adult themes…and not in a fun, sexy way.
On top of that is the fact that this isn't a book. It's a play. It asks its poor Muggle readers to conjure an entire stage production in their mind.