"We Were Liars" is a 2014 young adult novel by E. Lockhart. It tells the story of the Sinclair family, a wealthy and seemingly perfect Scots-American family who spend every summer on their private island. The plot centers around Cadence Sinclair, who suffers an accident at age 15 during one summer which causes memory loss. Two years later, her cousins and friends, known as "the Liars," help her recover memories about that summer, uncovering secrets, lies, and family trauma. The novel explores themes of consequence, privilege, family, love, and loss with a suspenseful, psychological mystery and an unexpected twist ending. The book received critical acclaim and won the Goodreads Choice Award for Best Young Adult Fiction. It was praised for its gripping and beautifully told story, complex characters, and clever plot construction. It was a bestseller and considered one of the best young adult books of 2014. The novel also has a prequel titled "Family of Liars" and a planned TV adaptation on Amazon Prime.

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