Robert de La Rochefoucauld, the titular character in Paul Kix’s new biography The Saboteur, probably would have been a badass even if he hadn’t become a spy or lived through the worst of World War II in France. Arrested and tortured by the Nazis multiple times, he seemed to have a preternatural ability to assume fake identities and lie when his neck was on the line. More than just a grizzled James Bond, he was a scion of one of France’s oldest and most respected families, with a fascinating story that would be unbelievable in fiction.

In the book, published this month, Kix, an editor at ESPN The Magazine, explains exactly what it meant for La Rochefoucauld to be a saboteur. The French Resistance had no standing army of its own, and the de facto leader for the movement, future president Charles de Gaulle, was stationed in London. The goal for the résistants, then, was to do everything they could to cause disorder, shut down factories, and hamper the Nazi war effort. After he was recruited to join an elite and covert band of British spies, La Rochefoucauld was present for major events of the Resistance, such as bombing a factory in Bordeaux and destroying a German battery at Pointe de Grave.

“He didn’t have to do any of this,” Kix told Vanity Fair. “He came from means. He could have easily fled to a more secure location during the Resistance, but he didn’t. And his family didn’t either.” Every time La Rochefoucauld escaped from capture, he went right back to the centers of Nazi torture in France. “He could have stayed as a member of the Resistance, but he could have done it in a supporting capacity. He decided to go right back to the worst of it. That’s what I wanted to figure out: why, why why.” In the book, he answers that question and many more, painting a gripping portrait of a person whose bravery doesn’t allow him to succumb to the pressures of the day.

Kix had never heard of the man he would spend years trying to understand while La Rochefoucauld was alive. “It was as simple as reading his obituary,” Kix said. Flipping through a copy of The New York Times a few months after La Rochefoucauld’s death on May 8, 2012, he saw a headline that caught his eye: Robert de La Rochefoucauld, Wartime Hero and Spy, Dies at 88. The obituary sketched out some of the details that Kix would spend years tracking down, about how La Rochefoucauld “frustrated Nazis, dressed as a nun, and sabotaged his way across Europe.” Kix thought the story sounded fascinating, but shelved it away because his life was in a state of upheaval. And besides, he didn’t even speak French.

But the possibility of telling La Rochefoucauld’s story to Americans tantalized him. “It kept nagging at me,” he said. “I thought, ‘Yes, I don’t know a whole lot about the French Resistance, and I grew up on a farm in Iowa, so I certainly don’t know about French nobility.’” Eventually he found a memoir that La Rochefoucauld wrote with the help of a journalist in 2002, and set to work, learning French in order to do research.

Robert La Rochefoucauld was 17 when the Nazi occupation of France began, and was affected by it from the very beginning. German soldiers moved into the family estate, though graciously allowed the family to remain there with them. Soon he went to Paris as a student and saw how profoundly and quickly the country changed when the collaborationist Vichy government came to power. “Robert was rebelling against what he saw taking place on the streets,” Kix said. “Regular Frenchmen began to either collaborate outright with the Germans, or were simply apathetic to the Germans.”

Kix thinks La Rochefoucauld didn’t fall into the same apathy because of his aristocratic family and the values they espoused. “Some of it has to do with the family lineage, and a sense that they were a part of something larger than themselves,” he said. “The family was the fourth oldest in France, and the La Rochefoucauld name is almost like the Kennedy name [in America], if the Kennedys had been around for 1,000 years. The name means a lot, and you have to live up to it. When I went through Villeneuve, the family estate where Robert grew up, there were busts of significant family members on display . . . Even though he was young, and even though he wasn’t studious, he had a certain amount of wisdom that [others] his age didn’t.”

He acclimated to spy work easily—taking on false names, stealing cars with little fanfare, and knowing when to lie and when to tell the truth. In his memoir and to his kids, La Rochefoucauld told stories of epic escapes, and when Kix began writing his own book, he knew he had to corroborate these seemingly tall tales. “I basically tried to scour everything,” Kix said. “I spent four years reporting this in five different countries.” He relied on journalists in Spain and Germany to gather information about where La Rochefoucauld traveled or was imprisoned during the war.

The most dramatic moment in The Saboteur comes when La Rochefoucauld steals at car to escape from Nazi soldiers as he is being led to his execution. Tracking this down was especially important for Kix. “I went to the Yonne department of central France, and I met a great local historian who had written a history of the Resistance,” Kix said. “He and I went through the prison rolls of Yonne through the occupation, and there was Robert’s name. Sure enough, it said évadé, escaped. I had these ‘holy shit!’ moments all the time.”

Ultimately, Kix found that writing about the life of Robert de La Rochefoucauld helped him understand more about the way the world has changed in the 21st century. “When there is a shift in what is acceptable behavior from politicians or leaders, it infiltrates into the general public, into the discourse,” he said. “Over the last five years, as I’ve researched this book, I’ve noticed how there has been a coarsening of our public dialogue . . . The Internet played a role, but what happened in France is not so different, insofar as anyone in susceptible to this change.”

La Rochefoucauld didn’t fall victim to that, it seems. “I hope the reader comes away from this with a sense of his bravery,” Kix said. “He knew in the closing days of the liberation that he had to be a part of it, and he made his own way.”