Shepard, Sara

After their friend Alison, missing for more than three years, turns up dead, four former best friends, each of whom had a secret known only by Alison, begin receiving frightening messages from someone identified by the letter "A.".

When one of their tightly-knit group mysteriously disappears, four high school girls find their friendship difficult to maintain when they begin receiving taunting messages from someone who seems to know everything about their past and present secrets.

Seventeen-year-old Sutton Mercer watches from the afterlife as her long-lost twin sister, Emma Paxton, continues to pretend to be her in order to identify Sutton's killer.

After their friend Alison, missing for more than three years, turns up dead, four former best friends, each of whom had a secret known only by Alison, begin receiving frightening messages from someone identified by the letter "A.".

Best friends Spencer, Aria, Emily, and Hanna find themselves under suspicion when the mysterious stranger named A tries to blame one of the girls for the death of their friend Alison and threatens to reveal the girls' darkest secrets.

Spencer, Hanna, Aria, and Emily, friends since seventh grade at the exclusive Rosewood school in Pennsylvania, find their history of telling small, convenient little lies catching up with them when a mysterious person named A begins making threats, hinting that he or she knows what really happened to their murdered friend Alison.

Former best friends Emily, Aria, Hanna, and Spencer continue to live in fear as they struggle to keep hidden even more secrets and someone new begins stalking them via their cell phones.

Hanna, Aria, Emily, and Spencer have been telling some outrageous stories, but no one seems to believe them, so when a killer comes after them, they wonder if the town of Rosewood will believe them.

When one of their tightly-knit group mysteriously disappears, four high school girls find their friendship difficult to maintain when they begin receiving taunting messages from someone who seems to know everything about their past and present secrets.

While Emma continues to investigate her twin sister's death, Laurel is sneaking around with her sister's ex-boyfriend.