Episode 1 of The Law According to Lidia Poet Season 3 opens six months after the events of the Season 2 finale. At Circus Laforet, a trapeze artist named Miranda Laforet requests her grandfather and ringmaster, Paride, to remove the safety net. Unfortunately, she falls to her death in the middle of her act.
Dr. Lidia Poet is giving a guest lecture on feminism to a class of female students. We learn that the Parliament is about to vote on her law and that she is now dating Fourneau, who is the Prosecutor General and is in good health. In the midst of her lecture, she reminisces about her old friend, Grazia, who had taken her in when she had run away from home and even funded her education. Grazia is a sly and charming lady who has arrived with her young daughter, Mila, to meet Lidia after nine years. As they walk, they see Lorena, one of the circus artists, being beaten and arrested for Miranda’s murder. Lidia quickly hands her Enrico’s card.
Lidia brings Grazia and Mila to her home and they catch up by drinking and dancing around. Soon, Grazia reveals that she needs help – she has a debt of 2000 lire and she cannot tell her husband. Lidia doesn’t have the money but promises to help. Grazia is impatient and seems crestfallen. Enrico and his wife, Teresa, show up following his visit to Rome. As usual, Teresa is quite inquisitive, insists on propriety, and is wary of Grazia. Lidia asks Enrico for the money but he cannot afford it, while wondering if she owes Grazia. A flashback shows the women taking a blood oath, and she quickly refuses.
The Laforets show up, and while exasperated, Enrico takes on Lorena’s case. The new prosecutor, Cantamessa, is pretty stubborn and has outdated ideas. Lorena was known for injecting Miranda with painkillers for her back pain. This time, the syringe had a heavy dose of a sleeper agent. Scandalous ads of Miranda with Lorena’s husband, Rubino, have Cantamessa theorizing that Lorena killed her out of jealousy.
However, Lorena viewed Miranda as an integral part of her family, while Rubino served merely as her mentor. Lidia believed that someone had murdered Miranda and framed Lorena. At home, Grazia made off with Lidia's jewelry, leaving a parting note behind. Lidia visited Fourneau, and while they flirted and kissed, he insisted that their relationship remain a secret to avoid spreading rumors.
Upon returning home, Lidia was overwhelmed by the sight of Grazia's robbery and Jacopo's presence. He was dating Conseulo, an opera singer who would be performing at the Regio. Lidia tried to hide her irritation as Jacopo hadn't written to her in the last six months.
Back to the case, Lidia discovered a shallow cut on Miranda's palm and realized that she too had taken a blood oath with someone. She told Enrico that it was a promise of everlasting friendship and honesty. A quick search revealed that the circus artist Susanna had the same cut. Lidia cajoled her until the girl claimed that Miranda was having an affair with Rubino. Rubino vehemently denied it but revealed that he had seen Miranda waiting for someone at the Regis. The Poets reasoned that Miranda had lied to Susanna because she must have been ashamed of whatever she was doing.
Grazia returned and finally spilled the truth. Her husband was controlling and abusive. She had been trying to run away but her border contact wouldn't take the jewelry as substitute payment. She also realized that she couldn't keep running forever. Lidia felt sad for her and promised to help. To cheer her up, Lidia took her to the Regis.
At the hotel, Conseulo grabs them to play a game of Never Have I Ever with the other guests. The drinking game reveals the playful relationship between Conseulo and Jacopo, which irks Lidia. She quickly shifts the focus to the case and soon learns of Calvart, a French circus manager who was invited by Miranda to sign with her but couldn't make it to the Sunday show (where she died). Fourneau offers to take Lidia to Vienna, where they can openly express their relationship without hiding. She agrees, but not before she resolves Grazia's situation.
A quick consultation reveals that domestic violence isn't considered a crime in this context and without evidence, a divorce is impossible. The optimistic Lidia believes she can convince Grazia's husband of a mutual separation. However, Grazia believes her husband will never let her go. This revelation strikes inspiration in Lidia as she realizes that someone knew of Calvart and didn't want Miranda to leave the circus. It must be someone who had no power and resorted to trickery - aka Susanna.
When Lidia confronts her, Susanna threatens to jump from the trapeze. But Lidia reveals that she can relate to her and had also felt betrayed when Grazia left her nine years ago to get married. Susanna starts crying, and Lidia realizes that she never meant to kill Miranda and it was an accident. Lorena is freed.
Lidia writes in her statement that an intense friendship can be dangerous, but a voluntary homicide charge for Susanna is unjust. Later, she hooks up with Fourneau while Jacopo is with Conseulo. Jacopo doesn't want to spend Easter with his family, and Conseulo realizes that he is avoiding Lidia. She believes that Lidia is in love with him and advises him to stop leading her on. He quickly changes the topic.
However, they do end up visiting the Poets. While Conseulo sings for the family, Jacopo and Lidia banter as usual. Both insist they are happy with their respective relationships, but their smiles are strained. Teresa is annoyed that Marianna dropped music and is focusing on her education in Paris. In the middle of the meal, Grazia's husband shows up, and we see that he is a captain. He speaks to Grazia privately, and Lidia frets the whole time. Finally, Grazia screams, and the Poets rush in to see that the Captain is dead. Grazia claims he tried to kill her.
