After a Prologue that shows us Mata Hari's corpse in the anatomy hall of the University of Paris (nobody had claimed it after her execution), the musical introduces Mata Hari performing her oriental dance, attended by an enthusiastic public, among whom are Puccini and his librettist Illica. Puccini is deeply impressed by her charm and beauty and sees in her his ideal of femininity.

Later he has a brief love affair with her after her unsuccessful performance in the Scala of Milan; he consoles her telling that even his "Butterfly" was booed in the same theatre.

 

Many years later, after Mata Hari's execution as a spy, Puccini conceives the idea of writing an opera about her. He is in a difficult moment of his life: the relationship with his jealous wife Elvira has become worse and worse; his publisher Ricordi pushes him to finish "Turandot" and finally he has serious troubles with his health. The memory of Mata Hari becomes a real obsession with him; in her he discovers aspects of all his opera heroines (Butterfly, Tosca, and Liù) and while working on his project he falls in love with the image he is creating.

  

But in her diary Puccini reads that also Mata Hari had lived an impossible love story that had caused her death. For a long time she had been exploiting rich men offering her body. But she realized neither fame nor money could chase away a deep sense of loneliness.

 

After falling in love - for the first time? - with a young Russian officer she needed money that could enable her to live with him for the rest of her life Therefore she agreed to spy for the French, not understanding that she was going to be involved in a situation she couldn't control. But she was sure that her innocence would be proved during the trial and that her lover would give decisive evidence in her favour. But he let her down, forgetting all his promises. And Mata Hari is sentenced to death. The public attending the trial comments on its issue: perhaps they needed a scapegoat.

 

While occupying himself with Mata Hari's life, Puccini is not able to keep his distance from the events he wants to tell, he feels very involved and sometimes wants to interfere, trying for instance to convince Mata Hari not to accept the offer of becoming a spy. But he must realize he can't change what already happened.

Finally Doctor Martini diagnoses a throat cancer at an advanced stage.

  

Having read Mata Hari's last words before dying ("Life is nothing...")Puccini can't do anything else but burn the few sheets he had written and reveal his own disappointment. He understands that just like Mata Hari he is sentenced to death. His opera about her will never be written.