Setsuna is ready to storm the gates of Heaven and rescue his sister Sara, but things are not that simple. He accepts help from the enigmatic angel Zaphikel, but finds a difficult price attached - Zaphikel is looking for someone to lead an army against the Angels and he wants Setsuna to head the charge.

Sara has her own plans for escape, but they also come with a price. And just when Setsuna thinks he knows everything about Angels, he discovers a terrifying new secret. Tensions are rising and Heaven is on the verge of war. Will Setsuna and Sara be reunited just in time to watch two armies of Angels tear their world apart?