A young adult novel by E. Lockhart. Cadence is the eldest grandchild of a privileged, beautiful family. The whole family spends every Summer on their private island. But something happened the Summer she turned fifteen, she and all the other Liars; her cousin Johnny, her cousin Mirren, and Gat, the nephew of her aunt's boyfriend and her own love. Cadence suffered a traumatic brain injury. Why? How? Why can't she remember what happened? Why will no one talk about it?
This was a surprising book. Spare prose. I do wish some explanation had been given as to why and how the four friends initially got the epithet "Liars". Other than that...it will stay with you.