Wisecracking idlers Wilkie (Spencer Tracy) and Mitchell (George Cooper) fail to dodge the draft as World War I intensifies in Europe, and are put to work shovelling manure at a US Army base. Their attempt at desertion backfires as they stow away on a troop ship carrying Air Corps pilots to France, and they blunder into war. Through constant run-ins with stern taskmaster Sergeant Hogan (William Boyd) and lewd flirtations with leggy troop entertainer Mary Way (Ann Dvorak), the two boys drift from one fix to the next. But when they unwittingly cause the destruction of a major German munitions depot, Wilkie and Mitchell are hailed as heroes. What could possibly go wrong as they fly home in triumph?