For seven hundred years the Immortal warrior Tain was held captive and tortured by a powerful demon, and retreated into madness to escape his pain. Set free by his brothers, Tain has wandered the world, but he's drawn to Los Angeles, a city divided by demon lords and vampire masters, the death-magic creatures barely kept in line by strict rules and the paranormal police.

Samantha Taylor, detective in the paranormal division, is committed to bringing down demons and vampires who turn too many victims. Her stakeout of a demon club is blown by the appearance of a man with amazing power, who kills the attacking demons with one burst of magic.

Samantha is shocked to see the man is Tain, the Immortal she helped rescue, whose healing touch burns her.

Tain is back, and he needs Samantha's help.

When the killer Tain hunts endangers them both, Tain and Samantha must solve the case together and fight the growing, powerful attraction between them, a battle they are steadily losing.