The following version of the novel was used to create this study guide: French, Tana. The Likeness. Penguin Books, July 17, 2008. Kindle.

In The Likeness, the second novel by Tana French in the Dublin Murder Squad series, detective Cassandra “Cassie” Maddox feels stuck in her new job in the domestic violence division of the police department after quitting her position in the Murder Squad. Bad experiences in her last murder case and the loss of a close friendship have left Cassie feeling at loose ends. Cassie is swept back into her role as an undercover officer when Lexie, a girl who looks just like Cassie and is using Cassie’s identity from Cassie's days as an undercover officer, is found murdered. Cassie gets too close to the case, wanting to be a part of the life that Lexie had lived. By doing so, Cassie is putting her own life in danger.

Cassie learned about the death of the woman using Cassie's undercover identity when her boyfriend, Sam O’Neill a murder detective, called her from the scene of the murder, making sure that Cassie was okay. When Cassie saw the victim, she was disturbed by how much the girl looked like her. Frank Mackey, head of undercover operations, wanted to take advantage of how much Cassie looked like the girl, whose identification indicated her name was Alexandra “Lexie” Madison. He proposed that police officers tell Lexie’s roommates that Lexie was not killed, only seriously injured and suffering memory loss. Even though Sam argued it was not a good idea, Cassie agreed to go undercover.

Cassie, whose parents died when she was only five years old, felt the first time she stepped into Whitethorn House, the house where Lexie had lived with her four friends, that she had come home. Daniel’s uncle had left him the mansion in his will. Daniel invited four of his friends — Abigail “Abby” Stone, Raphael “Rafe” Hyland, Justin Mannering, and Lexie — to live with him. All of these postgraduate students were either orphaned, grew up in boarding schools, or for some other reason grew up without a nuclear family. Cassie and Frank later learn that Daniel gave his friends equal shares in the house. Cassie, as Lexie, fits in seamlessly with the others. She feels she is part of a family.

During her time at Whitethorn House, Cassie learned that Lexie had been negotiating with Edward “Ned” Hanrahan, Daniel’s cousin, to sell her portion of Whitethorn House. Lexie had been pregnant when she was killed. Cassie believes that Lexie was planning to run away and raise the baby on her own. She could get enough money for her part of the house to cover her expenses.

On the same night that Cassie confirmed that Lexie had been negotiating with Ned, she and the others who lived at Whitethorn House decided to blow off some steam by getting drunk. Daniel drew Lexie off on her own and kissed her, a kiss with serious consequences. He confronted her the next day to tell her that he knew she was not Lexie. Cassie admitted that she was an undercover officer, sent to find out who killed Lexie.

Daniel told Cassie that Lexie was stabbed in the house, but he will not tell her who, specifically, stabbed her. Wanting to find out the identity of Lexie’s killer, Cassie refused to come in when Frank told her that her undercover role was over. She confronted Justin, Rafe, and Abby (who still believed she was Lexie) when Daniel was away and convinced them to tell her what happened the night that Lexie was stabbed. Daniel arrived and tried to interrupt the conversation, but Cassie pulled out her secret ammunition and told the group Lexie was pregnant and lost the baby because of the stabbing. Rafe indicated that was his baby, and cursed at Justin, apparently the one who did the stabbing.

Daniel hoped to keep Justin from going to jail and realized that his dream of living peacefully with his friends in Whitethorn House was finished. Because of this, Daniel pulled a gun on Cassie, knowing that she would have no choice but to protect herself if he fired at her. After Daniel shot at Cassie, she fired at him, hitting him in the chest and killing him.