Pretty Little Liars by Sara Shepard is about 5 best friends, Alison, Emily, Hanna, Spencer, and Aria. Ali, the head of the clique, made the four girls do terrible things and taunted them with their secrets. When Ali went missing, they began receiving messages from someone who knew everything from their past and the deepest secrets that only Ali knew.
Pretty Little Liars is a mysterious book because you don't know what's going to happen next which makes you want to keep reading.
I would definitely recommend this book to others who love high school secrecy and friendship.
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