To bring her dead brother back to life, the reckless thief Diana breaks into Lucifer's sanctuary and steals a magical orb. But the theft turns into a trap: the artifact's power ignites an uncontrollable desire in the demon, and after their night together, Diana discovers she is carrying the heir of Hell. Now she is a prisoner in a foreign world, hunted by Lucifer's jealous lover Lilith, while the ruler of Hell discovers love for the first time in his life. To save Diana and their son, he will have to sacrifice what he has never given up before: his immortality.
