Competing bush pilots join the Canadian Air Force, but two of them are too old and too wild for the training.
Bush pilot Brian MacLean (James Cagney) takes business away from Blimp Lebec (George Tobias), Tiny Murphy (Alan Hale), and Johnny Dutton (Dennis Morgan) by charging less. Emily (Brenda Marshall) expects Johnny but finds Brian landed. Brian takes up an old man, and the three planes come after him; but Tiny lands and goes into the trees because of Brian. Johnny lands too and picks up Tiny. Brian comes back to Emily, who refuses to help and then saves him from the lake. Johnny arrives with Tiny and quarrels with Brian, who is injured and collapses. Johnny goes for a doctor. In fog they light fires at night so that Johnny can land. The doctor (J. Farrell MacDonald) operates on Brian's head as Tiny gets sick. Johnny plans an airline, but Emily wants to marry him. Recovering Brian kisses Emily. Tiny tells Brian that he owes them, and Emily fails to keep Brian from leaving.
At Fort Wilson Brian worries about Johnny, who lands in a storm. Brian, Johnny, and Tiny are paid $4,000 each. Brian advises Johnny not to marry Emily and beats him in a fight. Brian flies to Emily and takes her to Ottawa. Johnny follows, sees her, socks Brian, learns they are married, and leaves, donating his airline money to charity. Johnny joins the Royal Canadian Air Force (RCAF). Brian leaves money with Emily and says goodbye. Brian learns Tiny and Lebec have no money to buy a plane and meets British Scrounger Harris (Reginald Gardiner). They hear Churchill on radio and fly to a RCAF airfield. An officer explains why they are too old for combat flying. They undergo training. Brian meets Johnny, who tests his flying and recommends him as a bomber pilot trainer. Brian teaches using instinct, and Johnny reprimands him. Brian flies too low, and the bomb damages the plane; he is dismissed by a court martial.
Brian drinks with Tiny. Air Marshal W. A. Bishop (himself) awards men their wings while Brian and Tiny buzz them. Tiny passes out and crashes. Johnny sees Emily and buys her a drink, saying Brian lost his civilian license. Emily says that Brian married her to protect Johnny from her. Pilots must fly bombers to England. Brian uses Tiny's license, and Johnny does not stop him. Scrounger is Brian's navigator. A German fighter plane shoots down Lebec's plane and kills Scrounger. Brian goes after the German against Johnny's orders and crashes into him.
This drama shows how in a war the reckless and violent
can become heroes if they are not killed first.