Clandestine weapons like the World War II FP-45 pistol, later dubbed the Liberator by the Office of Strategic Services in 1944, have always intrigued me. It remains the rarest of American martial handguns from the conflict, with original examples usually starting in the $1,500 range for rusty, damaged pieces and the best examples, with their impossibly rare waxed shipping boxes, bringing over $7,000. Myths and misinformation hide the pistol’s real story; they weren’t wildly inaccurate junk guns that exploded after a few shots, and they were never tossed out of airplanes over occupied Europe en masse. THE FP-45 PISTOL was...