<Tr> <Th> </Th> <Td> Television: (1994 - 06 - 06) June 6, 1994 (age 23) Rosewood, Pennsylvania </Td> </Tr> <Tr> <Th> Alma mater </Th> <Td> Hollis College </Td> </Tr> <P> Alison Lauren DiLaurentis is a fictional character and main antagonist in the Pretty Little Liars novel series, introduced in the original series of novels and also appearing in the television adaptation . In both the beginnings of the books and television series, Alison is a central character who is shown mostly in flashbacks . The entire plot of the series begins when Alison mysteriously disappears and leaves the small town of Rosewood in shock . Due to her position as a queen bee of Rosewood's social scene, Alison's actions and relations are constantly under scrutiny from the town's citizens . Sasha Pieterse, who portrays the character on screen, has described Alison as an indecisive person, even showing herself as a ruthless, manipulative girl . </P> <P> Throughout the first three seasons of the television series, DiLaurentis mostly appears in flashbacks and hallucinations . The character plays a more prominent role from the fourth season onwards . In the novel series, Alison is the main antagonist and "A", while on screen she changes her actions and turns out to be a victim too . Alison is the main antagonist for a portion of the fifth season of the television series, when she begins working against the Liars . Alison returns to being a protagonist by the end of the season, when she is arrested for Mona's murder and the Liars are kidnapped by A . </P>

When did alison go missing in pretty little liars
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