Things have changed for 17-year-old Zoe ever since the dramatic events that brought her together with the mysterious X took place.

To save Zoe and her family, X did the unthinkable - he won their freedom by giving himself up to captivity in the Lowlands forever.

But being back in the Lowlands has its advantages. It gives X the chance to discover his past, which could be the key to breaking the Lords' hold on him for good.

Little does X know that Zoe has a plan to reunite them - one that will see her risk her life and bring her perilously close to losing all that she and X are fighting for.