After recently sharing their hopes for a possible reunion, Lucy Hale, Troian Bellisario, Ashley Benson, Shay Mitchell, Sasha ...

Alison DiLaurentis, played by Sasha Pieterse, was the leader of the four liars before she disappeared. She often bullied and manipulated people, including Spencer, Aria, Emily and Hanna.

From the very eventful night Alison DiLaurentis disappeared to the three-year-long senior year, the Pretty Little Liars timeline is pretty confusing.

Freeform / Via giphy.com So, in honor of Sasha for giving us the ultimate bad girl character, here are 15 of Alison DiLaurentis's most iconic moments from Pretty Little Liars.

The series begins with Alison DiLaurentis (Sasha Pieterse), the school mean girl, disappearing after a sleepover with her friends, Spencer Hastings (Troian Bellisario), Hanna Marin (Ashley Benson ...

Sasha Pieterse thinks a cameo as Alison DiLaurentis on Pretty Little Liars: Summer School could answer some seriously open-ended questions about her character — and allow for the Emison reunion ...

Thousand-mile stares have become commonplace with Alison DiLaurentis (Sasha Pieterse), the blond catalyst of Pretty Little Liars, as she wrestles with how she got here: two murdered family members ...

Alison DiLaurentis is finally getting out of jail on the Pretty Little Liars premiere, and she'll soon be making a new friend within the police department. Check out all this week's Mega Buzz!

At the beginning of Pretty Little Liars: The Perfectionists, Alison was desperate to leave her past behind her and start a new, calm, drama-free life in Beacon Heights.

Alison DiLaurentis, the OG missing blonde girl on Pretty Little Liars, played into this idea from the beginning of the show.

Alison DiLaurentis’ mysterious disappearance has been at the center of “Pretty Little Liars” from the beginning, and after four seasons in hiding, the former queen bee returned in Season 5 ...

The character, whose identity has remained a mystery throughout the ABC Family drama’s sixth season, revealed his face to Alison DiLaurentis (Sasha Pieterse) during prom at the end of Tuesday ...