Unforgotten (Jessica Brody Trilogy)

Some memories are better left forgotten.
After a daring escape from the Diotech scientists who created her, Seraphina and Zen believe they are finally safe from the horrors of her past. But new threats await them at every turn as Zen falls prey to a mysterious illness and Sera's extraordinary abilities make it more and more difficult to stay hidden. Meanwhile, Diotech has developed a dangerous new weapon designed to apprehend Sera―a weapon that even Sera will be powerless to stop. Her only hope of saving Zen's life and defeating the company that made her is a secret buried deep within her mind, a secret that Diotech will kill to protect. And it won't stay forgotten for long.
Packed with mystery, suspense, and romance, Unforgotten is the riveting second installment of Jessica Brody's Unremembered trilogy, and delivers more heart-pounding action as loyalties are tested, love becomes a weapon, and no one's memories are safe.