Bored and unhappy as the Lord of Hell, Lucifer Morningstar abandoned his throne and retired to Los Angeles, where he has teamed up with LAPD detective Chloe Decker to take down criminals. But the longer he's away from the underworld, the greater the threat that the worst of humanity could escape.
Lucifer must find the antidote to the Professor's poison before it kills Chloe. He travels to hell to find the Professor's soul and get him to turn over the antidote. While he's there, he is forced to confront his guilt about Uriel's death. Mom heads to hell to get Lucifer back, but Lucifer still feels betrayed by his parents because of something he discovers.