Leaving the outskirts of Rome, Annalena goes to a middle-class neighborhood where she meets professor and writer, Alessandro Piperno. He talks about what it was like growing up there and about his identity as a writer.

Lojacono goes to Letizia's trattoria and tells her about the bad news about the witness. She tries to reassure him but also has a new customer to attend to. Francesco can't let Giorgia go and sleeps in the car in front of her house.

How are the harvested truffles divided up? And besides being sold whole, how are they further processed? Paolo and Stefania tell us the story.

After her trip to the Tiber River, Camilla goes to pick up Livietta at Giulio's house, where the two kids are dancing to Merengue. Camilla has some questions about that. Meanwhile, Berardi and Torre are busy with the coroner, identifying a corpse.

Melania Mazzucco grew up in a part of Rome on the outskirts, not the part people usually associate with the beautiful city. The white Fiat 500 her father bought for the family became an important part of her life.

Varricchio is back in the DA's office and tells a different story, admitting he had lied the first time. But is there proof of his new version? At home, Lojacono is shocked by some news he hears on the TV.

Truffle hunting is a peculiar activity, one that requires the collaboration of a dog. And you never want to let on how many truffles you find, even if you are friends with other truffle hunters.

The mouse is still an issue at Camilla's house. At police headquarters, Berardi has his hands full with the mother of the murdered detective and Mattioli's wife.

Melania talks about her relationship with her father when he was still alive. He didn't say much, but unbeknownst to her, tried to get a story of hers published. She talks about one her favorite parts of Rome: Isola Tiberina (Tiber Island), the only river island in the part of the Tiber that runs through Rome.

Ottavia and Palma talk about his new apartment and the fact that it is still empty. Lojacono gets some good news from his friend Paolo and shares it with Marinella. He goes to the train station to wait for Laura and gets an idea about the case.

This episode is about a specialty from Colonnata, a little village above Carrara, where marble is quarried. It's pork lard, which may not sound very appetizing but is beloved by Italians all over the peninsula. A little goes a long way, but savored with typical unsalted Tuscan bread, it is pretty special. And marble plays an important part.

Camilla, in conversation with her mother, hopes that the postcard from New York is just a misunderstanding. Renzo has a moment of truth by a dumpster. Later, he says something about Dr. Mattioli that gives Camilla an idea about her "hallucinations."

Melania Gaia Mazzucco talks about one of her novels set in seventeenth-century Trastevere, quite a different place than what we see today. Although she has traveled the world, Mazzucco comes from generations of romani di Roma (Romans from Rome).

Lojacono is not at all convinced that Varricchio killed his own children, especially after talking to him. Pisanelli got some bad news about another retiree having taken his own life. Pisanelli had been watching over the wrong home.

Armando talks about how the works of Duchamp influenced his work and that of so many contemporary artists. The choice of a unique exhibition hall played a part, as well.