Unbelievable (Pretty Little Liars #4) by Sara Shepard

"Behind Rosewood's grand facades, where the air smells like apples and Chanel No. 5 and infinity pools sparkle in landscaped backyards, nothing is as it seems. It was here, back in seventh grade, that five best friends shared everything--Seven jeans, MAC makeup, and their deepest, darkest secrets. For Aria, Spencer, Hanna, and Emily, it was a dream come true . . . until Alison, the most beautiful of them all, suddenly vanished.
Now someone named A has turned their charmed lives into a living nightmare. Emily has been shipped off to her hyper-conservative cousins in Iowa. Aria is stuck living with her dad and his home-wrecker girlfriend. And Spencer fears she had something to do with Alison's murder. But Hanna's fate is far worse than all of that--she's clinging to life in the hospital, because "she knew too much."
With A's threats turning dangerous and Ali's killer still on the loose, the girls must uncover the truth--about A, about Ali, and about what happened to Hanna--before they become A's next victims. But as they unravel Rosewood's mysteries and secrets, will it bring an end to the horror . . . or is this just the beginning?"

So much drama! I totally enjoyed the whole novel and it was completely breathtaking. Betrayal and many more issues occur, it just takes you through a stimulating ride throughout the whole book. It was thrilling and unpredictable for me, there was just so much action described in the story and the mystery never ends! Without a doubt, I would recommend this book and would rate it a 4.5/5.