In idyllic Rosewood, four very pretty girls just can't help but be bad...

Hanna will stop at nothing to be Rosewood's queen bee. Spencer's digging up her family secrets. Emily can't stop thinking about her new boyfriend. And Aria approves a little too strongly of her mom's taste in men.

Now that Ali's killer is finally behind bars, the girls think they're safe. But those who forget the past are doomed to repeat it. And they should know by now that I'm always watching.