The explosive, untold true story of the band of patriotic FBI agents who went undercover to hunt down U.S. traitors on foreign soil during World War II and later investigated war criminals in the lead-up to the famous Nuremberg trials—a riveting real-life spy thriller from the bestselling author of The Last Battle . . .

They collaborated with Nazis and Fascists. Conspired against Allies in World War II. Committed unthinkable acts of treason. And triggered a secret manhunt as harrowing as any Hollywood cliff-hanger. The mission was part of the FBI’s “European Operation.” The targets were U.S. citizens plotting against their own country. The goal: to identify and capture these traitors hiding in the shadows of war-torn Europe. To accomplish this, a small group of federal agents assumed new identities to infiltrate underground networks, interrogate key suspects, and expose the enemies within the Allied ranks. It is one of the most fascinating spy stories of World War II—and one that’s never been fully told. Until now . . .

Using newly declassified documents obtained through the Freedom of Information Act—as well as exclusive interviews with family members of the FBI agents and unpublished accounts of American citizens accused of treason—this meticulously researched book provides shocking new details behind this crucial World War II operation. From J. Edgar Hoover’s attempt to expand FBI operations overseas to the agency’s covert ties to Britain’s MI5; from the shocking exposure of espionage activities in France and Italy to the final convictions of Nazi war criminals at the Nuremberg trials—this incredible saga of spy and counterspy is brought vividly to life by author Stephen Harding in what is destined to be a classic of World War II literature.

G.I. G-Men is a must-read for military and history buffs, espionage fans, and anyone who loves a great adventure story.