Fifth grader Penny, who doodles to cope with anxiety, worries that her best friend is drifting away.

On trial for murdering an actually still-alive Alison DiLaurentis, only Aria, Emily, Spencer, and Hanna know they've been framed and resolve to beat Ali at her own game.

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 missing friend's body is found and another of their friends commits suicide, four former best friends live in fear of their secrets being exposed by someone who is stalking them via their cell phones.

"Amanda, Ronnie, and Lauren all arrive at the Silver Swans preschool Welcome Breakfast with something to hide. Amanda is running away from a past on the East Coast she cannot afford for the other parents to discover. Lauren is recovering from a post-partum condition her husband has warned her not to disclose. And Ronnie is hiding herself and her daughter from the one man who could at any moment appear in their lives and ruin everything she's worked...

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.

After high school juniors Spencer, Emily, Hanna, and Aria think they've seen Ali, their missing and presumed dead friend, they pursue clues from a mysterious stalker, trying to find out if she is still alive.

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.

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...

"It's spring break, and the pretty little liars are trading in Rosewood for a cruise vacation. They want nothing more than to sail into the tropical sunset and leave their troubles behind for one blissful week. But where Emily, Aria, Spencer, and Hanna go, A goes, too. From scuba diving to tanning on the upper deck, A is there, soaking up all their new secrets. Emily is smooching a stowaway. Aria's treasure-hunting partner is a little too interested...