When the succubus Lorelei sees the angel Azaziel from across the bar, she knows he's been cast out of Heaven, but is not yet Fallen. She resolves to do whatever it takes to bring the angel down. She trails him back to his lair in the warehouses outside of downtown Los Angeles, where they seduce each other. Together on the streets of L.A., they encounter Ashleigh Johnson, one of Azaziel's mortal charges, dying of hepatitis in the street. The angel rescues Ashleigh's soul from two harpies poised to devour it—then uses it to possess Lorelei. Other angels don't foresee any positive outcome to any of this. In their eyes, their brother has endangered a mortal soul and compromised his own standing in Heaven. When they intrude, Lorelei flees—taking Ashleigh along for the ride. Lorelei's sister Floria tracks down a defrocked priest willing to exorcise Ashleigh's mortal soul from Lorelei's infernal flesh. The intimate little ritual swells into a virtual Who's Who of Hell's presence in L.A.!

If Romeo had wings and Juliet a barbed tail, could they find happiness in the City of Angels? After their escape from the ashes of Lost Angels, the succubus Lorelei and the angel Azaziel want nothing more than to enjoy each other's company. Unfortunately, Asmodeus, the Demon Prince of LA, has threatened to devour Lorelei's new-grown soul if she doesn't bring about Azaziel's downfall. Meanwhile, Aza is keeping secrets of his own that threaten the tenuous peace between Heaven and Hell. Three archangels come to town to try to set things right, but friendships are fracturing. The demon in charge of fallen angels is sniffing around. And Los Angeles is about to be caught between a devil and the deep blue sea.