Three cousins joined by a nephew of one of the adults lived all summer long on an island off Martha's Vineyard, their own island with three huge houses and two beaches, with motor boats, kayaks and cooks and servants. They never talked about their lives off the island, at school. They always obeyed their parents. No one had problems, or if they did these were not spoken of. They are the liars. Something changed the summer of fifteen (the year they were fifteen). It wasn't just that grandmother had passed away the previous winter. It wasn't just that Cady was madly in love with the nephew and grandfather did not find him acceptable. It wasn't just that the aunts were angry and arguing. But that was part of what happened.
As the story opens Cady is back on the island the summer of seventeen not having been there the previous summer and not remembering much of what happened that fateful summer of fifteen and suffering horrible migraines. There is a gleaming new house where once there was an old wooden mansion filled with memorabilia, all of which is gone. One aunt roams the island all night long. One of the little cousins has terrible nightmares and the liars meet at one house where slowly Cady's memories return and the awful events of summer fifteen are revealed and Cady recovers from selective amnesia and grieves inconsolably. The reader remembers along with Cady and is horrified along with her and left a bit breathless in the end. And perhaps we come to understand just a bit the importance or lack of importance in things, money and what controlling, manipulating others can lead to. Definitely read this, even if your background isn't that of the incredibly wealthy.