When you have “defied gravity” and waited for the new Bad: Part One movie hits theaters, the pain is over – you’re going to Shiz!

Led by Cynthia Erivo and Ariana Grande as Elphaba and Glinda, the two-part film adaptation is directed by Jon M. Chu. It is a kind of double adaptation: based on Stephen Schwartz and Winnie Holzman’s stage adaptation of Gregory Maguire’s 2007 novel. Released on the big screen on November 22. Bad: Part One is rated PG by the Motion Picture Association.

Before you head down the yellow brick road, be warned that there are spoilers ahead.

Wicked: The Life and Times of the Wicked Witch of the West by Gregory Maguire first hit shelves in 2007. The book asks the central question posed by the musical and the film: are people born evil, or is evil forced upon us? But that’s about where the similarities end.

The film and the musical both focus largely on relationships: between Elphaba and her sister Nessa, Glinda and Elphaba – not to mention Boq (Ethan Slater) and Fiyero (Jonathan Bailey).

But the book spends far more time laying out the social, political, and ethical conditions in Oz, as well as the nature of good and evil, than it does on the entanglements of its characters. Young readers and those looking for a mostly light-hearted story about friendship and acceptance need not apply: some seriously adult themes, including sexual violence, political unrest, infidelity, racism, and the role of religion in society, are all present throughout .

While the musical and film versions contain some terrifying moments – many involving flying monkeys baring their teeth and breaking through windows to get to Elphaba and Glinda, as well as a scene showing how the monkeys grew wings – the book is more insidiously disturbing and can leading to questions from younger children that their parents are not quite ready to answer.

The book also covers a much longer timeline. The book is divided into five different sections, based on the location where they take place, and takes the reader from Elphaba’s birth and its circumstances (which are much darker in the book than in the musical or the film), her time with Shiz, her journey around the Wizard, five years later when she lives in the Emerald City, seven years later (after spending a year unconscious and another six years mute and homeless), and seven years later when Dorothy moves into a house Nessa drops. The rest, as most of us know, is Wizard of Oz history.

Bad: Part One ends with many Broadway aficionados’ favorite song: a stirring rendition of the inspiring “Defying Gravity.” For those who know the play well, the film ends where the first act ends. It’s still about 2 hours and 40 minutes (which is about the length of the entire Broadway show).

But take heart, and maybe take a preemptive bathroom break: that’s considerably less time than it would take you to read it.