If you aren't already obsessed with the Netflix adaptation of Jay Asher's cult favourite book, 13 Reasons Why, then prepare to lose your heart and quite probably a lifetime supply of tears too.

But if you havealready consumed the entire series, then you might just have noticed these major plot changes that Selena Gomez and her production crew made during the adaptation of the show from page onto the screen.

*WARNING: THIS INCLUDES MAJOR SPOILERS FOR BOTH THE BOOK AND TV SHOW, OBVIOUSLY*

1. The timeline changes

In the book Clay receives the tapesand then immediatelylistens to all 13 sides in one go over the course of a singlelong/highly caffeinated night. That's not the case in the Netflix show and instead they stretch the course of events out over several days. Tony even remarks that Clay is taking his sweeeet time stretching out the listening process - way longer than any of the other reasons before him.

2. Hannah's parents and the school lawsuit

In the originalwe don't know muchabout Hannah's mum and dadand how they are dealing with the tragedy of her suicide. Instead they are peripheral characters. But on screen much more development is given to their experience as parents who have lost their daughter and Kate Walsh (who you probs know best as Dr Addison Montgomery from Grey's Anatomy) gives an incredibly heartbreaking performance as Hannah's mum as she tries to understand what happened to make Hannah decide to take her own life.

Towards the end of the show they even decide to sue the school to get answers, which leads each of the kids involved in the tapes into having to perform depositions. Things don't escalate in this way in the book.

3. The POV is wider

In the book things aretold from Clay's point of view as he listens to Hannah tell her story. In the Netflix show, the story spans much wider and we really get to see how the other people featured on the tapes are dealing with events and their involvement in Hannah's death. We see Jess coming to terms with being raped, Justin's family background and him coming to terms with what he did to Jess and how Zach and Courtney's family pressures have made them react to events the way they do.

Basically there's just more to the characters: we get to understand why they made the choices they did and how they react when they realise the ripple effects their actions had on Hannah.

4. Clay and Jeff's relationship

The show adds a whole new dimension to Sheri's actions as in the book, while Clay is first on the scene following the car accident that results from the knocked down stop sign, he doesn't personally know the person killed. In the show we meet Jeff and see how much of an impact his friendship had on Clay, making it that much more heartbreaking when we find out he died in the accident.

It also adds another element of guilt to the situation for Clay because of the way he reacts to Hannah trying to show sympathy following Jeff's death. Not realising her part in events, he accuses her of basking in the drama to which she has no right, having not known Jeff the way he did. This doesn't happen in the book but is pretty gut-wrenching when you see it play out on screen.

5. Sheri and Jenny's characters are merged

In the book we meet a character called Jenny, a cheerleader who encouragesHannah to take part in the matchmaking fundraiser for Valentine's Day. In the show, this character is replaced by Sheri, who we then meet again when we find out that she then gives Hannah a lift home from the party, knocking over the stop sign that eventually causes the accident killing Jeff. In both versions of the story Sheri refuses to immediately report the incident to the police despite Hannah's pleas.

6. Courtney is gay

Courtney's story is explored in much greater depth on screen than it is on paper. Instead of Hannah and Courtney giving each other backrubs while trying to lure in Tyler, who has been taking photos through Hannah's window, she is actually revealed as having romantic feelings for Hannah and asbeing gay. Herstruggle to come to terms with her sexuality becomes the reason she does not want details of the tapes to come out.

7. The order of the tapes changes

One of the most notable plot devices that's changed up on screen is the ordering of the tapes. While Clay's tape is number nine in the book it is delayed to be number 11 in the show, meaning that he should technically pass the tapes onto Bryce. He skips Bryce and instead passes the tapes straight to Mr Porter.

8. Clay considers what could have been

The show brings more to Hannah's relationship with Clay and plays more on what could have been if he had acted even slightly differently. We see the introduction of idealisedvisions where Clay behaves how he wishes he had - by taking more chances, being braver and sticking around even when Hannah pushed him away. It's a classic case ofwishing you'd have known then what youdo now and an extremely powerful interpretation of it too.

9. Things are more explicit

One of the most interesting things about the Netflix depiction of this story is that they've not held back or tried to sugarcoat things. These are terrible events and they are portrayed as such. There is no room for Hollywood glamourising and it's refreshing to see that, particularly something aimed at the YA audience where censorship is usually greater.

But it's by no means an easy watch as a result. Not only do we see Hannah's suicide in all its horrificdetail,but wesee some extremely shocking scenes where both Hannah and Jess are raped by Bryce. In the book, Hannah's rape is implied and alluded to, but she does not recall it in detail in the way we see it when he physically overpowers and assaults herin the hot tub.

10. Alex attempts suicide

While Alex seems wracked with guilt in both versions of the story, the Alex from the show is seen to be reacting to his feelings in a much morephysical and shocking way. Not only does he struggle to fit in with the others trying to protect their reputations, but he himselfattempts suicide as the show plays out. This results with him in hospital in a critical condition, something that doesn't happen in the book.

11. Clay records Bryce's confession

Upon hearing Bryce's tape, Clay decides to confront him - something that doesn't happen in the book. Not only does Bryce beat him up pretty horribly, but Clay goads him into confessing what he did to Hannah: something he records on tape suggesting there is evidence that can be used to show people what Bryce did.

12. The fate of the tapes

This leads on from the point above and instead of mailing off the tapes to reason number 10 as he does in the book, Clay has evidence he shows Tony that incriminates Bryce. He also takes the tapes to Mr Porter and confronts him directly about the way he failed Hannah. Tony too takes action and gives over his copies of the tapes to Hannah's parents to help them understand and give them to seek asmall sliver of justice on Hannah's behalf.

13.Skye has a much bigger part to play

Then ending of the book and show have similarities but are very different. In the show we learn much more about how Jess, Justin and Alex have dealt with the events surrounding Hannah's suicide. There's an implication about what will happen to Bryce and then there's Tyler, who is seen with a gun hidden in his room. But instead of finishing the story with Clay merely calling out to a passing Skye, in the show he actuallyasks her to hang out and we see them, Tyler and Tony all driving away together.

Skye's character is also developed in much greater detail as the show progresses:with her trying to help Clay when the other students hide drugs in his bag, with him confronting her about her self-harming and their altercation discussing why they grew apart during high school. In the book she is more of a peripheral figure and only really appears when Clay bumps into her on a bus in the middle of the night and again when he seeks her out, concerned for her mental health in the book's final pages.

'Find out the vid below to find out what advice Selena Gomez gave Katherine Langford on the set of 13 Reasons Why...'