Sometimes bad things happen to bad girls. . . . Aria's love life is on the Fitz—ahem, fritz. Emily's exploring her wild side. Hanna's kissing the enemy. And someone from Spencer's past—someone she never thought she'd see again—is back to haunt her. But none of that compares to what these pretty little liars did on their last spring break. It's their darkest secret yet. And guess who else knows? I haven't forgotten, and I certainly haven't forgiven. These pretty little liars better watch their backs because they're about to get exactly what they deserve. . . .