Ian Thomas was friends with Jason DiLaurentis. He used to date Melissa, but secretly also dated Alison, in addition to kissing Spencer. After Melissa and Wren broke up, he and Melissa eloped. After finding out about Ian's obsession with video taping people in private situations, Spencer and her friends believe that Ian is Alison's killer after seeing a video of him and her together the night that she died. When trying to kill Spencer for knowing too much, he is killed by A, who later took his body and set up a fake suicide for him.

Pretty Little Liars Quotes

Alison: It's like you went to sleep one night and forgot who I am.
Aria: I know exactly who you are. A.
Alison: Stop saying that.
Aria: Why should I? You're A! You stole the game from Mona and then you killed her because she had proof.

You think the truth is this big shiny disco ball of purity then go ahead and try it. See what it gets you. Telling the truth to the wrong person at the wrong time is how I ended up where I did. Take it from me you're always better off with a really good lie.

Alison