Alison DiLaurentis is one of the boldest characters on popular teen series Pretty Little Liars, and the truth about her disappearance is compelling.

One of the key mysteries of Pretty Little Liars is what happens to Alison DiLaurentis (Sasha Pieterse) and why she left Rosewood in the first place. The teenager is considered the 'Queen Bee' of her small town and is known for being a mean character who takes pride in knowing her best friends' secrets and sharing them at awkward and upsetting times. In the pilot episode, it appears that Alison has been murdered, but when it is revealed in season 3, episode 24 "A DAngerous GAme", that this isn't true, there are many questions surrounding where she has been and what she has been doing.

Throughout the show's seven seasons, there are hints and clues about the identity of the person who has been stalking the main characters, and many people are "A" throughout Pretty Little Liars. While the dangerous threat of "A" is why Ali disappears and why her friends are frightened by the situation that they are in, they end up making even more enemies along the way. Ali's character arc is one of the most thought-provoking parts of the popular teen series and the twists and turns make for a gripping story.

Mona Helps Ali Disappear After Her Mother Buried Her Alive

In season 4, episode 24, "A Is For Answers," Ali explains to her friends in New York City that Mona Vanderwaal (Janel Parrish) helped her leave Rosewood. The night that the girls have a sleepover, which is shared through flashbacks in the pilot, Ali's mother, Jessica (Andrea Parker), knocks her out with a rock and buries her. While she is eventually rescued by Mrs. Grunwald (Meg Foster), it was Mona who convinced Ali to hide at the Lost Woods resort, create the alias Vivian Darkbloom, and to leave Rosewood.

While this was quite a shocking scene initially - especially since Mona is revealed to be "A" in the season 2 episode "UnmAsked" - it did make a lot of sense as helping Alison disappear showed why Mona was able to increase her social status and get closer to the Liars. This detail also emphasized how emotionally manipulative Mona could be as she realized that Alison was in a vulnerable position and used her fear of being killed to her advantage.

Bethany Young Was Buried Alive, Not Ali

Although Alison was revealed to be alive, the viewers soon learned that a murder did take place on that night as Spencer Hastings's (Troian Bellisario) older sister, Melissa (Torrey Devitto), shares that she buried Bethany Young (Jessica Belkin) alive after she thought that Spencer murdered Ali. Not only was this one of Pretty Little Liars' shocking plot twist, but it was also key in CeCe Drake's arc (Vanessa Ray) as the two met at Radley Sanitarium together, which Bethany eventually escaped after stealing her identity (as she wanted to punish Ali and CeCe's mother, Jessica, for secretly dating Bethany's father).

Why Pretty Little Liars Made It Appear That Ali Was A

When Ali shares why she ran away from home at the end of season 4, this is a shock as the other characters had assumed that Ali was "A". Since Ali was also seen to bully her friends (and many of the students before leaving Rosewood), it also made sense that she would be "A" as every text message that the Pretty Little Liars characters focuses on a dark secret that they don't want anyone finding out (but Ali was often aware of). Although the show's red herrings could be frustrating, this is a clever one that makes for a better viewing experience.

Ali Returns To Rosewood In Season 5

Ali comes back to Rosewood in season 5, episode 2, "Whirly Girl" and she pretends to the police that she was kidnapped and held prisoner for two years. The questionable Rosewood police department doesn't appear concerned about Ali's well-being, and while Ali's friends are upset that she is asking them to withhold the truth, Ali later says that she didn't want the police to know that Aria killed Shana Fring (Aeriél Miranda) - a minor PLL villain. Since an "A Team" member texted Ali that they would share this information if she wasn't careful, Ali took this threat seriously and attempted to be a good friend.

Ali's friends are angry at her return, as they have become stronger and more confident in her absence and they don't like that she wants to take control of their lives the way that she always did. If she didn't want them to lie and cover up that she actually left out of her own volition, they might welcome her with warmth. Instead, Aria, Spencer, and Hanna are unsure if Ali is still playing games.

Ali and Emily's Pretty Little Liars relationship is another compelling part of her return home. Because Emily has had romantic feelings for Ali for years, she wants to go along with Ali's plans and doesn't see a problem with lying. Once Ali makes it clear that she loves and misses her friends, and once everyone realizes that "A.D.", who ends up being Alex Drake (Bellisario), is the real threat, the characters can work as a team. However, while Emily and Ali's romance is moving and Ali shows some changes, she never fully explains where she was hiding for two years, which is a thread that Pretty Little Liarsleft hanging.

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