"Lucifer's" overarching plot is a journey of self-acceptance disguised as a crime procedural. The central mystery is not the weekly murders, but Lucifer himself. Key twists across the seasons build upon this idea. In Season 1, it's revealed that Chloe Decker is immune to his charms, a puzzle that drives his initial fascination. The solution is revealed later: Chloe is a "miracle baby," blessed into existence by Amenadiel on God's orders, making her literally a gift from God in Lucifer's path.
Season 3's climax, where Chloe finally sees Lucifer's Devil face, is the series' most critical turning point. Her initial terror and subsequent acceptance become the foundation for his ability to finally accept himself. Season 4 explores the fallout, with Lucifer's self-hatred manifesting physically, turning him into a monster until Chloe's love proves to him he is not one. His selfless return to Hell at the season's end shows he has finally learned responsibility.
Season 5 introduces his twin brother, Michael, who impersonates him and forces Lucifer to confront his own identity and flaws. The season culminates with Lucifer's ultimate sacrifice for Chloe, flying to Heaven and burning up to resurrect her, an act of selfless love that makes him worthy of becoming the new God.
The final season's twist reveals the cause of his future mysterious disappearance: his future daughter with Chloe, Rory, travels back in time, angry at him for abandoning her. The resolution of this paradox is the series' ultimate revelation: Lucifer realizes his true calling isn't to be God, but to return to Hell and heal its inhabitants, helping them overcome their guilt. He must abandon his daughter and Chloe to fulfill this purpose, creating the very future Rory resented. The finale reframes the entire series: Lucifer's time on Earth wasn't a vacation, but an education. He was learning empathy and understanding pain so he could become the universe's therapist, turning Hell from a prison into a place of rehabilitation.