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.

After their friend who has been missing for more than three years turns up dead, four former best friends continue to receive frightening messages from someone who knows damaging secrets about them.

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.

Seventeen-year-old Emma Paxton steps into the life of her long-lost twin Sutton to solve her murder, while Sutton looks on from her afterlife.

High school seniors Aria, Emily, Hanna, and Spencer have all done horrible things -- things that would put them behind bars if anyone ever found out. And their stalker 'A' knows everything. So far A has kept their secrets, using them to torture the girls. But now A's changed the game. Suddenly the girls are hauled in for questioning, and all their worlds begin to unravel. If A's plan succeeds, Rosewood's pretty little liars will be locked away for...

Watching from beyond the grave while her long-lost identical twin, Emma, assumes her identity, Sutton Mercer witnesses the discovery of a dark family secret and realizes that someone from Emma's past may be her own killer.

"Sutton Mercer had the perfect life, great friends, and a gorgeous boyfriend...until someone murdered her. Then the killer forced Sutton's long-lost twin sister, Emma, to pretend to be her. Now Sutton can only watch from beyond the grave as Emma frantically tries to figure out who killed her sister, and why. But when Sutton's body is discovered, Emma's time is up--and she becomes the number-one suspect herself."--Publisher's statement on Amazon.com....

Former best friends Hanna, Aria, Spencer, and Emily, who lost their best friend and leader, Alison, years ago when she disappeared, find themselves in grave danger when they pursue the truth about Alison.

Struggling to return to normalcy after surviving Alison's attempt to kill them, Spencer, Aria, Emily and Hanna endure a series of disasters before realizing that they are being stalked by a new "A" who knows all of their secrets.

When Emma Paxton steps into the life of her long-lost twin Sutton to solve her murder, she finds new suspects at every turn, while Sutton looks on from her afterlife.