The location of the notorious Glimera penal colony was lost after raids. When a freak accident tells Nyx where her sister might be, she decides to find this hidden underground labyrinth no matter what. Embarking on a journey underground, she learns the terrible truth... and meets a man who will change her life forever. The Jackal has been in the colony for a long time and no longer remembers what happened in freedom. Caught in circumstances beyond his control, he helps Nyx because he is unable to help himself. After she discovers what happened to her sister, trying to get Nyx out of the colony becomes their number one goal. United by passion, they come up with an escape plan for Nyx... even though they will never be together again. And when the Black Dagger Brotherhood is called to help and Rhage discovers that his half-brother has been imprisoned on false charges, the treacherous Warden plans death for them... for everyone, even the Brothers.