A morning news host interviews Joan about Odin Reichenberg's crimes and his trial, three years after Sherlock's "death." Odin was sentenced to life in prison, but he was never charged for Sherlock's murder. Joan wrote "The Casebook of Sherlock Holmes." She' now has a son, Arthur. Marcus is now Captain Bell. Attorney Ronald Adair comes to tell Joan Jamie Moriarty is dead. She bequeathed a package to Joan as Sherlock's heir. Joan goes to smash Sherlock's headstone, a signal for him to return. Sherlock tells Joan that Moriarty isn't dead. He's been foiling her efforts under various identities, and she figures out Sherlock's alive. So she sent a stooge to lure him out. Adair is found shot to death. Sherlock said he dropped out of contact with Joan to protect Arthur. Joan had told Gregson and Marcus that Sherlock was alive. Adair sent $200,000 to Hernan Zielenko, who claims it was a poker debt. Sherlock said it isn't Moriarty who's luring him out of hiding. Ellory, Moriarty's lieutenant, tells Joan that they knew Sherlock is alive. Moriarty didn't have him killed because Sherlock was hurting her enemies even more. Sherlock tracks the cardroom where Zielenko played, where he meets NSA Agent McNally. He figured out Sherlock was alive based on all the criminals being gift wrapped for local police. He wants to hire Sherlock to do the same thing for the NSA. Sherlock meets Arthur. He tells her about McNally's offer. Sherlock goes to meet with Gregson, who hugs him. Sherlock tells him that he relapsed just after his disappearance. Gregson lets Sherlock know Joan has cancer. She's about to start chemo. Sherlock tells her he's staying. One year later, Sherlock is graveside. McNally approaches him about the job, but Sherlock refuses him. Joan and Sherlock visit Marcus about becoming NYPD consulting detectives again.