Every family has secrets. Mine, yours, Daniel Guiet’s.

But I can pretty much guarantee that Guiet’s family secrets are more explosive than yours. Guiet, along with Timothy K. Smith, explores his father’s covert missions during World War II in Scholars of Mayhem: My Father’s Secret War in Nazi-Occupied France.

“My father’s life was exceptional for his generation and his era,” Guiet says. “But for my wife and I, especially for me, the journey of discovering and unearthing it was really remarkable. It pretty much has lasted my entire lifetime.”

In 1943, at barely 19 years old, Daniel’s father, Jean Claude Guiet, was plucked out of U.S. Army Airborne School. Before his paratrooper boots were even issued, he found himself in the lobby of the Willard Hotel in Washington, DC. When a military truck pulled up, Jean Claude, and a few other people in civilian dress, climbed in. He didn’t quite know what he was getting himself into, but he had just joined the Office of Strategic Services, the wartime precursor to the CIA.

Ten months later, he was parachuting into France as part of Britain’s “Special Operations Executive” (SOE) ready to sabotage Nazi efforts and aid the French Resistance. After the war in Europe ended, Jean Claude was sent to the Pacific Theater by the OSS and then spent something close to two decades in the CIA, undertaking missions that are still classified today.

But as a kid in the 1950s, Daniel didn’t know any of this. All he knew is that his family moved around a lot—Washington, DC, Saipan, Manila, and more—and his parents didn’t seem to have a lot of friends.

Also, his father had a tin bread box that almost never left his side.

After nosiness got the best of five-year-old Daniel, he looked in the box. He didn’t understand most of what he found: a gun, knives, “a length of wire with a wooden handle at each end,” and tiny pieces of paper filled with random letters and the heading “Field Station to Home Station and Home Station to Field Station.” Daniel also found passports and identifications cards that held his father’s photo but different names.

Daniel still doesn’t know much about his father’s post-war work for the CIA, but his exploits during the war are filled to the brim with heroism. Jean Claude played a key role in “Operation Salesman,” an effort coordinated by the SOE, a top secret organization created by Winston Churchill and otherwise known as the “Ministry of Ungentlemanly Warfare.” Jean Claude’s mission was to help coordinate Resistance sabotage efforts so Allied troops could leave the beaches of Normandy and advance toward Germany.

Many of Jean Claude’s SOE colleagues were captured, tortured, and killed by the Nazis. Villages that aided the Resistance were razed and their inhabitants slaughtered. Firefights, mortars, Nazi roadblocks, and traitors within the Resistance were a constant concern. Jean Claude cheated death too many times to count.

And he hardly said a word about it for 50 years.

Most of the relevant files weren’t declassified until 1997, and that’s when Jean Claude slowly spoke more and more about his experiences.

Daniel gave Jean Claude a computer for his 74th birthday and said, “Write your story.”

He could have written half a dozen memoirs about his adventures. But most of what Jean Claude wrote concerned his time in France. The more he wrote, the more he opened up. Soon he would spend hours at the computer, filling discs with information that very few people knew.

“As he was writing it triggered some kind of increased comfort,” Daniel says. “So I started drawing him out. Sometimes he’d smile and not answer. Other times he would give a six- or ten-word answer. Other times he would open up and start talking almost like he was teaching himself how to verbalize what he’d compartmentalized.”

The memoir opens in the year 2000, with Jean Claude reconnecting with Bob Maloubier, a fellow agent on “Operation Salesman” he hadn’t seen since the liberation of Paris. The two men talked through the night and then the next day, and the next, and the next, weaving together stories of tragedy and heroism. Daniel and his wife were there to hear it all. And decades after five-year-old Daniel nosed into that tin breadbox, the rest of the world can finally take a peek inside.

Richard Z Santos is a writer and teacher in Austin. His fiction, essays, and interviews are widely published.