"Careful of the Grim" is etched into the cold stone walls of the Halcyon City Prison-a warning, threat, and reminder that we all die.

But what about living?

And which one should we fear more?

Mara Castten is an assassin-intelligent, calculated, and lethal. Being the top female angel within her Order demands it. She has built her reputation by being ruthless and wild, earning a nickname widely known and feared by all.

Mara has spent over three hundred nights imprisoned after completing an assignment she should have gotten away with. Now she is shackled-by chains that ground and keep her restrained-while they drain her magic, which desperately yearns to burst free.