Lucifer and Marcus strike a deal to find a way to kill Marcus, and Lucifer wants to learn Marcus' mental and physical vulnerabilities. When the opportunity arises for Lucifer to pose as Marcus' husband, Lucifer leaps at the chance. Meanwhile, Maze smells something different on Charlotte.

The author of a science-fiction YA novel series is murdered, and Lucifer believes her missing manuscript could let him overcome his own "block" against thinking of a way to kill Marcus. Meanwhile, Maze invites Amenadiel and Linda on a double date.