Biographical note:

E. LOCKHART is the author of four books about Ruby Oliver: The Boyfriend List, The Boy Book, The Treasure Map of Boys, and Real Live Boyfriends. She also wrote Fly on the Wall, Dramarama, and How to Be Bad (the last with Sarah Mlynowski and Lauren Myracle). Her novel, The Disreputable History of Frankie Landau-Banks, was a Printz Award Honor Book, a finalist for the National Book Award, and recipient of the Cybils Award for Best Young Adult Novel.

Country of final manufacture:

US

Main description:

A beautiful and distinguished family.
A private island.
A brilliant, damaged girl; a passionate, political boy.
A group of four friends—the Liars—whose friendship turns destructive.
A revolution. An accident. A secret.
Lies upon lies.
True love.
The truth.
 
We Were Liars is a modern, sophisticated suspense novel from National Book Award finalist and Printz Award honoree E. Lockhart. 
Read it.
And if anyone asks you how it ends, just LIE.