Pretty Little Liars

Pretty Little Liars was published in 2006 and began a young adult series that eventually ran to sixteen novels and a set of companion books. Sara Shepard was writing for television before she turned to fiction, and the series was conceived as a long-form mystery with a single central question that could be sustained for years: who is sending the messages, and what happened to Alison?

The novel is built on four separate secrets. Spencer is competing with her sister, Aria has come back from a year abroad with something she cannot talk about, Emily is dealing with a friendship that has become something more, and Hanna is working out what she is willing to do to stay popular. Shepard moves between them in short chapters, and the suspense engine is that the reader is always slightly ahead of one girl and slightly behind another. The adult world in the book is largely absent or indifferent, which is what leaves the girls managing the situation themselves.

The series spent sixty-two weeks on the New York Times bestseller list in its various volumes and was adapted into a long-running television series, which took the plot well past the books and changed the answer to the central question. The original novels remain a starting point for the contemporary young adult thriller, and this is the first of them.