Pretty Little Liars 4 Books Box Set Collection By Sara Shepard, Toxic Series 4

Deadly
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 good. . . .

Crushed
High school seniors Aria, Emily, Hanna, and Spencer have been tortured by A for too long. Now they're determined to take the fight to A . . . even if it's the last thing they do. As the rest of Rosewood prepares for the prom, the girls drop everything in their hunt for A. But with each new piece of evidence, A only seems farther away. No matter how close the liars get, A is always one step ahead--and ready to crush them completely. 

Vicious
High school seniors Aria, Emily, Hanna, and Spencer have been through a lot since their best friend, Alison DiLaurentis, disappeared five summers ago. A stalker named "A" has harassed them for their past mistakes and revealed their darkest secrets to the world. They've been on TV, hounded by the press, kicked out of school, arrested, and even put in jail. With time running out, and their lives on the line, one of the Liars does something so terrifying and shocking, fans will be left breathless.

Toxic
High school seniors Aria, Emily, Spencer, and Hanna barely survived their most recent encounter with A. And it's not over yet . . . The police don't believe that the real A is still out there, but the girls know what--and who--they saw. If they don't track down this final tormentor soon, A will silence them forever.