Netflix’s new series “13 Reasons Why,” produced by Selena Gomez, is set to premiere on Friday, but before jumping into the drama filled show, it is important to note that this story is based on the book of the same name.

From “Gossip Girl” to “Pretty Little Liars” to “Shadowhunters,” when a book is turned into a series the exact plot line is not always followed. Although adapted shows typically portray important moments from the book, endings are sometimes altered, characters are changed and at times just altogether left out. 

(Spoiler alert: The end of the “13 Reasons Why” book is revealed below.)

The book, a New York Times bestseller written by Jay Asher, follows the life of a shy teenage boy named Clay Jensen who comes home from school one day to find a box with his name on it sitting on his porch.

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Upon examining it, he discovers there are cassette tapes inside from his crush and classmate Hannah Baker who committed suicide two weeks ago. On these tapes, Hannah explains why she chose to commit suicide and gives 13 reasons for her decision.

Clay begins to listen to the tapes and goes on a journey in which Hannah explains that she blames thirteen people for her suicide. These people — whether they were fellow classmates, friends or faculty — all betrayed Hannah in some way with the exception of one person. However, the identity of this individual is not revealed until later on.

The tapes detailed Hannah’s life which consisted of bullying, sexual assault and violation of privacy. After dealing with all the ups and downs, Hannah finally reaches out to her high school counselor and reveals that she wants to kill herself.

Hannah records the conversation with the counselor where he tells her that if she is not willing to press charges against the student who assaulted her then she should simply move on.

Finished listening to the tapes that detailed what caused Hannah to end her life, the book comes to an end when Clay sees a female classmate who is seemingly isolated from the rest of the student body. Believing that she is on the verge of committing suicide, Clay reaches out to her as an attempt to help her in a way that he could never help Hannah.

“13 Reasons Why” was originally released in 2007, but in the 10th anniversary edition of the book, Asher revealed an alternate ending that was never published until December 2016. In this ending, Clay returns to school still dealing with how Hannah was treated by others.

While leaving school, he is stopped by a classmate who reveals that Hannah’s parents found her after she took the pills and rushed to her to a hospital, which means Clay’s classmate is still alive. Upon hearing the news, Clay leaves to be with Hannah at the hospital.

Which ending will the series choose? Fans will have to watch to find out. “13 Reasons Why” premieres March 31 on Netflix.