Spencer stole her sister's boyfriend. Aria is brokenhearted over her English teacher. Emily likes her new friend Maya . . . as much more than a friend. And Hanna's obsession with looking flawless is literally making her sick. But the most horrible secret of all is something so scandalous that the truth would ruin them forever.

"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...

The stalker's identity has finally been revealed but high school juniors Spencer, Emily, Hanna, and Aria seem condemned to repeat the past as they resume their unrepentant ways.

"It's springtime in Rosewood, but while everyone else is searching for the perfect prom dress, Hanna, Spencer, Emily, and Aria are on a different kind of hunt: They're looking for A ... Hanna puts her campaign for prom queen on the back burner to volunteer at a burn clinic, where one of A's victims is recovering. Emily digs into Ali's past at the mental hospital with some very crazy consequences. Spencer contacts an amateur private eye to help her...

It's finally summer in Rosewood, Pennsylvania, which means afternoons at the pool, high school graduation -- and the end of the scandal that has rocked the town for years. Or so everyone thinks. It's been weeks since police caught the notorious stalker and murderer known as A. But Hanna, Aria, Emily, and Spencer know that the real A is still out there. And as long as A is on the loose, nothing can ever go back to normal ... if there is such a thing...