Pretty Little Liars
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The season 5 finale of ABC Family's "Pretty Little Liars" will give fans a major clue to the 'A' riddle that has been plaguing fans since season 1.

The Liars will finally find out A's identity in the finale, but fans of the show will only be given a clue as to who the hooded villain is. As showrunner Marlene King previously revealed, a number of fans have correctly guessed A's identity, but no one has figured out the motive behind A's actions.

'A' has been on the show since the premiere, and he/she is someone who has always stayed in the background so as not to attract much attention. But why would 'A' be hell-bent on hurting the Liars? A quick scan of fan forums throws up interesting theories.

According to Tumblr account prettydirtysecretliar, 'A' is someone who has been hurt by Alison, and his/her intention in targeting the Liars must be because they played a small part in whatever Alison did.

"Marlene has said we will feel sorry for A when we learn his/hers story. That leads me to believe that Ali have done something seriously bad to this person or the persons family. And the girls must play a minor role in this, like helping Ali cover it up, or just that they stayed friends with her, and needs to suffer. A has had multiple chanses to kill the liars, but have not atempted to, but it seems like A would really like to kill Ali, after causing her some trouble."

Could Hanna have stolen the A game from Mona? If A's main target is Alison, then Hanna has a good reason to be the hooded villain. Alison has always been mean to Hanna regarding her weight issues and her animosity towards the other Liars could be because they don't always have her back.

Also, Hanna and Mona have always been best friends and even when the others found out that Mona was 'A', Hanna always stuck to her. "When the girls found out Mona was A, Hanna still defended her. Saying that she was constantly tortured by Ali. She even continued visiting her in Radley, and ALWAYS offered excused for her," pointed out Tumblr user rosewoodtheories101.

Season 5 finale of "Pretty Little Liars" airs Tuesday on ABC Family.