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 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.

The stalker's identity has finally been revealed, but Spencer, Emily, Hanna and Aria are bound to repeat the past, and continue to be bad.

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.

Fifth grader Penny, who doodles to cope with anxiety, worries that her best friend is drifting away. Why does the cubby room always smell like farts? Who etched the words "I Am Bug Man" inside my desk? Why is Mom suddenly acting like she has a secret? Nobody said starting fifth grade would be easy, and Penny Lowry's anxiety means a million questions are always spinning through her thoughts. Luckily she's got a lot to look forward to, like her favorite...

Tired of being blackmailed by a stalker who is tormenting them with threats of revealing their darkest secrets and biggest mistakes, high school seniors Aria, Emily, Hanna, and Spencer team up to fight back.

"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...