Who Is "A" on Pretty Little Liars? Meet Our Top 12 Suspects

Why It's Possible:

• Spencer disappears along with Alison the night of her murder, and we don't know where she goes.
• During flashbacks to that night, we find out that Spencer and Ali got into a huge fight just before Ali's disappearance.
• She's a Hastings. She has the smarts, the cunning, and the financial means to pull something like this off.
• Spencer is not accounted for just before the lodge fire. Could she have started it?
• Spencer has a dark side and even joins the "A" team very briefly.
• When Alison and Emily have a secret rendezvous in season four, and when Spencer shows up, Ali frantically runs away.

Why It's Not Possible:

• Spencer is so devastated when she thinks Toby is dead and again when she thinks Toby is on the "A" team.
• Spencer finds Ravenswood and the "A" lair. Why would she show them both to the girls if she was "A"?
• Remember when Mona admits she's the original "A"? Well, let's not forget she proposes that Spencer join the team, and Spencer turns her down.