au meme: pretty little liars as psychological thriller; spencer hastings suffers from a mental disorder, which only her family and her best friend, alison, know about. alison pretends to believe in spencer’s hallucinations but one day she gets bored with her own game and tells spencer the truth. the girl, driven by pure rage, kills her friend and, feeling guilty, blocks the whole situation out of her mind. after some time, she and her friends start getting anonymous messages, blaming them for alison’s murder. having told her parents the story of them being blackmailed, she gets sent to psychiatric care, where she is healed from the hallucinations of the three girls - hanna, aria and emily. she seems to have been recovered well and tries to start her life all over again. she even meets a boy - toby, who she starts a relationship with. unfortunately, she starts getting the -A texts again and is more and more suspicious of her new boyfriend. she sees a hallucination of toby in her house, wearing a black hoodie, and, feeling utterly betrayed, kills him. it turns out that, unable to deal with the guilt after killing alison, she created an alter ago, -A, that, as if her conscience, tormented her with all the secrets she held from herself and others.