When Tzadkiel, an angel of justice, accidentally kills two innocent people, he quits his job. His self-imposed retirement, however, doesn't last. Semyaza, leader of the Watcher angels, wants Tzadkiel to find a missing Watcher.
The case soon becomes a murder investigation. Tzadkiel suspects ties to a gunrunning operation. Not only is Semyaza arming terrorists in the Middle East, he also plans to unleash a deadly weapon on the world. But Semyaza's weapon turns on him, and he loses control of it. Unless Tzadkiel and his team stop this threat, they may find themselves annihilated along with humanity.