Lucifer toys with a murder victim while Chloe and Maze investigate the death. Meanwhile, Amenadiel cleans up the club, and Linda mothers a genius.
Lucifer visits one of the new arrivals in Hell, explaining that he is in Hell, and has been murdered numerous times already whilst being stuck within an endless loop in which he re-lives his death as punishment for his crimes. Meanwhile, topside in Los Angeles, Decker, Ella and Maze work to solve the murder. Ella explains that she is angry that Lucifer ghosted her to “see family”, whilst both Maze and Decker attempt to deal with the pain all whilst keeping his true location a secret.
Lucifer takes a keen interest in the case when he realises that the man died in Los Angeles, and it is highly likely that Chloe will be on the case. Lucifer explains that as the ruler of Hell, he is in a unique position to help him solve the murder. The two set out to solve the murder.
Amenadiel, has taken up Lucifer’s job at the helm of Lux, and is keen to change the reputation. He notices a drug deal taking place in the distance and rushes to end it. The following morning, he reports this to Dan, citing that there is a real crime taking place that the two of them could end.
Simultaneously, Lucifer begins working on the case at the same time as Decker and Maze. The latter two attend an elite poker game hosted by “Dirty Doug”, in which they question Doug over the loans he hands out and what they often mean for the recipients. When people at the game begin realising that they are with the LAPD, one of Doug’s men begins running, causing both Decker and Maze to chase him. Eventually, he is hit by a car and killed, allowing Lucifer to send a message to the surface, citing that “it's safe where you stored it” — Decker is confused by this but is warmed by the sign from Lucifer.
Lucifer quickly grows tired of helping solve the murder and, believing to have done his part, announces that he is to go back to rule Hell and end the charade of solving the murder. Lucifer takes pity on Lee and decides to help him, taking him back to the root of his Hell loop: his sister’s baby shower. It was the last family gathering before his parents died. Lee never joined the party because he didn't want to disappoint them by being close due to his criminal life.
Meanwhile, Decker finally figures out the message from Lucifer, and explains to Maze that they need to visit a storage locker owned by Lee. When they arrive, they find Lee’s sister, Meg, waiting for them. She explains about the safe, and further explains that she misses Lee; a sentiment that both Decker and Maze relate to Lucifer. Maze kisses Decker on a misread signal, and Decker realises that they’ve been using the partnership to fill the void left by Lucifer.
Doug's men attack Decker and Meg, thinking they have the money Lee owed; the safe was empty. Meg laughs at their idiocy; they knew Doug couldn't hold onto his money. A shootout ensues, which sends a shooter to hell. While Lucifer is snapping at Lee for comparing their lives, a demon brings the shooter; Lucifer learns of Chloe's plight.
Lucifer helps Decker take out Doug’s men, explaining that things are different now and that time isn’t linear in Hell; he isn't the same old devil she knew. Whilst it has been two months on Earth, thousands have passed in Hell. Afterwards, it is shown that Lucifer told Lee that he will not return to Earth, therefore it is unknown who has returned in his stead.
- Tom Ellis as Lucifer Morningstar and Mysterious Doppelgänger
- Lauren German as Chloe Decker
- D.B. Woodside as Amenadiel
- Lesley-Ann Brandt as Mazikeen
- Kevin Alejandro as Dan Espinoza
- Rachael Harris as Linda Martin
- Chasten Harmon as Megan Garner
- The events of Really Sad Devil Guy takes place between June 3rd 2019-June 5th 2019.