The Maestro gives his final instructions: the tempo, the characters, the mood. A moment to focus, then the piano begins to play, followed by the singers’ voices. Il Bufalo, Il Dandi, Il Terribile, the doomed victim: his execution is about to take place. You can feel the drama building. And then it happens. Nicola Piovani conducts, completely absorbed, until the scene ends.

“Good. Well done.” The rehearsal ends in a burst of relieved applause. Sitting beside him, writer and former magistrate Giancarlo De Cataldo lets out a sigh. “I’m ecstatic.”

At the Maggio Musicale Fiorentino, a sprawling maze of rooms and corridors, there is a palpable buzz of excitement as young professionals from around the world clear their throats and hit the right notes. The premiere of Romanzo Criminale is set for Oct. 23 and will be broadcast live on Rai 3, followed by three more performances through Oct. 31. Directed by Massimo Popolizio, the production features music and conducted by Maestro Piovani and a libretto by De Cataldo, who published the story nearly 25 years ago. Against all his expectations, it became a phenomenon: the rise and fall of the gang that ruled Rome in the 1970s and ’80s first became a cult novel, then a successful film (“When I saw it for the first time, I pinched my legs to make sure it was real”), and finally a hugely popular TV series. Now comes the challenge of turning it into an opera.

The proposal came about two years ago from Carlo Fuortes, then Superintendent of the Maggio Musicale Fiorentino and former Rai CEO. The idea was to offer a story capable of attracting a new audience beyond opera’s traditional fans. “I accepted enthusiastically,” De Cataldo recalls. His passion for opera has grown stronger in recent years, but it runs deep in his family. “My father, from the province of Taranto, would steal a horse to ride into town to hear the opera. He knew Verdi by heart.”

The composer and the writer already knew each other. They had even watched a few Roma soccer matches together. But they weren’t close — not yet. And before agreeing to the project, Piovani had a few questions for him.

“We arranged a lunch, and I asked Giancarlo to bring me the book,” recalls the Oscar-winning composer. “I brought the libretto of I Vespri Siciliani: it’s this tiny little thing, yet the opera lasts for hours. We had to turn more than 600 pages into an opera libretto. I asked him, ‘Tell me in a few words what Romanzo Criminale is about — the dark fairy tale at its heart.’” De Cataldo did exactly that, and Piovani was convinced. “He told me a magnificent story,” the composer says. There was just one last question: “As a writer, how flexible are you?”

De Cataldo laughs at the memory. “I’m not the kind of writer who guards every comma from the intrusion of the composer. Quite the opposite: the libretto must be shaped around the music. And I love teamwork.”

The partnership was ready to begin. There was only one thing left: telling Fuortes. But why make it easy? “Carlo, I had lunch with Nicola, but he wants nothing to do with it. He doesn’t like the idea, and I think he doesn’t like me either,” De Cataldo joked over the phone. Disappointment at the other end of the line, followed by laughter. And so began a collaboration that both men now look back on with enthusiasm, a journey that has brought them here, into the hushed rooms of the grand Tuscan theater. In one, the director is rehearsing; in another, the chorus; and in another, the star, Basque-born soprano Vanessa Goikoetxea, whose sublime voice and commanding stage presence have captivated everyone.

In the transition from novel to libretto, it is Patrizia, the prostitute played by Goikoetxea, who takes on the role of narrator.

“It’s easier to draw out the lyrical quality from this woman, a prostitute with a loving side, an inner world erased by cynicism,” Piovani says. “And then she is Rome — the great she-wolf who nurses, watches from above and mourns her dead. She is the one who closes the opera, and she remains alive, because Rome is eternal,” De Cataldo adds.

Of the novel’s many characters, eight will appear onstage, played by artists from around the world — Costa Rica, Mexico, Chile and Croatia. “In a world where everyone talks about identity, the beauty of this environment is that it’s cosmopolitan,” De Cataldo says. The one thing they have in common, Fuortes points out, is the Italian language. But opera is also the only art form, De Cataldo and Piovani say with a shiver, “where you risk getting booed.”

What do they hope will come from the experience?

“My goal is to have four good performances, where the people who come to the theater connect with it and are moved, at least a little,” Piovani says. He has composed music for 220 films and is now working on his third opera, guided by the mantra, as De Cataldo puts it, “that the audience has to understand what is happening onstage.”

For the writer, the experience has been exhilarating. “I will always be grateful to Romanzo Criminale, and in a world where everyone complains, I’m grateful for the life I’m living.”

Fuortes interjects: “They won’t say it, but the hope is that there will be a second run,” in addition to the one already scheduled next year at Rome’s Auditorium.

And looking even further ahead?

“I’d like to start thinking about another opera,” De Cataldo ventures.

Piovani shoots him a look. “That’s bad luck. We’ll talk about it after the second performance.”

For now, it’s time to get back to rehearsal.