The following version of this book was used to create this study guide: Osman, Richard. The Man Who Died Twice. Pamela Dorman Books, 2021. Kindle Edition.

As the narrative begins the members of the Thursday Murder Club are at a café. A waitress, who does not seem to fit the role of a waitress, is serving them. Her name is Poppy. The conversation turns to the pros and cons of Joyce getting a dog. Elizabeth, however, is not giving the conversation her full attention because she is thinking about a letter that she received from a person whose identity she created when she was an MI5 agent, and whose death she later orchestrated. The person who wrote the letter wants to meet with her. Elizabeth gives Joyce advice about adopting a dog and decides to meet the author of the letter.

It turns out that Elizabeth’s ex-husband, who is an M15 agent named Douglas, wrote the letter. He is in a safe house under protective custody because the diamonds that were in the home of a man who acts as a middle man for criminals were stolen. He accuses Douglas of stealing them, and he wants them back. MI5 assumes that he is innocent, but Douglas confesses that he stole the diamonds and wants Elizabeth to help protect him. Elizabeth agrees; however, in exchange, she wants information about a teenager named Ryan, a man who leads a gang which assaulted Ibrahim after the meeting in the café.

Elizabeth recruits the members of the club to help her protect Douglas. However, they are not the only ones protecting him. The waitress from the café turns out to be an agent who is installed in Douglas’ safe house. Two other agents named Sue and Lance are also on the case. Soon afterward, Martin sends a hit-man to kill Douglas. Poppy, kills him. MI5 moves Douglas to another safe house. He contacts Elizabeth, and she and Joyce go to see him. They find the corpses of Douglas and Poppy.

Now the team has a murder case to solve, and they want to find the diamonds. In addition, they want to bring Ryan, the person who is the head of the gang that assaulted Ibrahim, to justice. They work with Chris and Donna, who are members of the police force. Chris and Donna know Ryan is guilty, but they cannot keep him in custody. Additionally, they cannot arrest the woman he works for, Connie, even though they know she is guilty of heinous crimes.

Douglas has left Elizabeth a clue as to where the diamonds are located. She figures it out, but she is not the only one. Poppy overheard the conversation that Douglas had with Elizabeth and shared the information with Sue. It turns out that Sue was Douglas’s girlfriend and accomplice in the theft of the diamonds. However, afterward she realizes that Douglas still loves Elizabeth and is not going to run away with her and the diamonds. He is going to keep them for himself and hope to win Elizabeth back. So, she kills him and Poppy because Poppy knows too much.

Elizabeth figures out that Sue is the killer. She finds the diamonds, gets money for them, and donates it to research to find a cure for Alzheimer’s disease, the disease from which her current husband suffers. Chris and Donna arrest Ryan and Connie with the help of the team.