Watch Me (Book One in The Shatter Me Series 2) by Tahereh Mafi

James Anderson had a plan.
Or half of one. All that matters is he managed to do what his older brother, the famous Aaron Warner Anderson, never did: infiltrate Ark Island, the last refuge of The Reestablishment. No outsider has breached the stronghold of the authoritarian regime, but James is in. In a prison cell, sure, but as far as James is concerned, a win is a win.

It's been ten years since the fall of The Reestablishment, when the notorious duo--Juliette Ferrars and Aaron Warner Anderson--led a worldwide rebellion and established The New Republic of the West. But The Reestablishment is ready to make a devastating move, and they have the perfect assassin for the job.

Rosabelle Wolff had a plan.
She always has a plan. On Ark Island, where constant surveillance is packaged as security, even emotions must be experienced with caution. And when she's given an order to kill, she never hesitates.