Alison DiLaurentis

Alison DiLaurentis is a main character in the series and the best friend of Hanna, Aria, Spencer, and Emily. In the television series she was the Queen Bee of Rosewood High School, before mysteriously disappearing only to be found dead three years later. In the book series, her life is stolen by her twin sister Courtney and she is sent to a mental hospital in Courtney's place before returning to kill Courtney and regain her old life back.

She is portrayed by Sasha Pieterse.

Physical Appearance
In the book, Alison is described as beautiful, with a heart-shaped face framed by long blond waves and big blue eyes.

Television Series
In the series, Alison is portrayed by Sasha Pieterse. Much like in the book, Alison is the most beautiful and popular girl in Rosewood, and is the envy of many. She surprisingly befriends Hanna, Aria, Spencer and Emily who previously considered themselves un-cool; together they become the most popular girls in school sharing sleep-overs, pool parties and shopping trips with each other. Ali knows each of the girls' biggest secrets and constantly teases them or hints about them in conversations. In the summer after 7th Grade, Ali holds a sleepover in Spencer's barn with her best friends Spencer, Hanna, Emily and Aria. She convinces them to let her hypnotize them, only Spencer disagrees and the two get into a heated argument outside, which ends up with Ali running into the woods and meeting someone by the kissing rock. She goes missing, presumed dead and for a year her body is never found. The new owners of the DiLaurentis's house (who moved away after Ali vanished) decide to get rid of the Gazebo in the backyard and construction workers discover Ali's remains in the ground below it. Alison shot a video of herself and Ian before she went missing. "A" managed to show the Liars the entire video of Ian apparently choking her to death.

Ian Thomas

 * Started: Before Pilot
 * Ended: Before Pilot
 * Reason: Her death.

Friends
Alison is the ring-leader of her group of friends, which consists of Hanna, Aria, Spencer, and Emily. Alison disliked Mona Vanderwaal, who her friends constantly made fun of. Alison treats Hanna like her lackey and Emily is hinted to be more than a friend.