Pretty Little Liars by Sara Shepard

 

I don't know if you've heard of the ABC Family Original Series Pretty Little Liars but the books are almost as good. Aria, Alison, Emily, Hanna, and Spencer are all best friends. One summer Alison disappears during a sleepover. Alison was one of the only reasons why they were friends, now that she's gone the girls start living their own lives.
Aria just came back from three years in Iceland and soon falls for her English teacher, Ezra Fitz. Emily starts to gain feelings for the new girl. Hanna has her own problems of shoplifting with her new best friend Mona. And Spencer starts liking her older sister's boyfriend, Wren.
But someone knows their secrets and keeps reminding them of it through messages signed with a single "-A". The four girls are left trying to find out who A is and how they know so much about them. Could it actually be Alison?
There are some small differences in the books and the television show. One such difference is Wren's last name which in the book is Kim but is Kingston in the show. Spencer's, Emily's, Aria's and Hanna's hair color are different from their hair colors in the show. Emily is an only child in the show but in the books she does have siblings. There are more differences but for the most part the book and show follow similar guidelines as of now.
There wasn't much that I would change in the book. But Ezra's character was not really likeable in the books. And other characters felt kind of distant at times. Overall, it was mysterious enough to make me want to read the next book.