A British girl (Victoria Shaw) broadcasting for the Germans as a double agent obtains codes and frequencies for the Allies.

A dishonorably discharged flier (James Franciscus) masquerades as a replacement pilot in order to fly one combat mission.

When Gallagher and a pilot who resents him are shot down over the North Sea, they're rescued and treated with surprising decency by a U-Boat commander -- but the Nazi turns out to have a sinister hidden motive.

The 918th is being chewed to pieces while attempting to bomb a target in Norway, so secret that even Joe Gallagher doesn't know what it is or why it's so important. In fact, in its latest try, the mission commander, Col. Christie, decides to abort and turn back only 4 minutes from the target after losing 8 out of 21 bombers, with 4 more heavily damaged, including his own. Infuriated by the excessive losses and secrecy surrounding the missions, Joe alienates his superiors when he aggressively defends Christie against a looming court martial. To the rescue, possibly, rides his father, Lt. General Gallagher, who is hellbent on getting his son his first general's star. But Joe is in no mood to discuss promotion with his friend and the reputation of the 918th teetering on the edge of oblivion.