Geoff Carter (Cary Grant) is co-owner and operator of an airline whose business it is to deliver the mail high in the mountains in Chile. The route is treacherous and only the most skilled aviators can go through the mountain pass, and only if the fog has lifted. A man serving as a lookout lives in a hut in the mountains, and keeps in contact by radio. His word is law—when he tells them not to come, they don’t come.
One day a young woman wanders into their airport while waiting for the next boat to leave the harbor. She’s on her way to Panama to find a singing job, and she hangs out with the pilots while she’s waiting. Her name is Bonnie Lee (Jean Arthur) and all the guys want to buy her dinner. Joe, the guy who wins the coin toss and therefore, the pleasure of her company, is called away to take the mail over the mountain. After he takes off, word comes from the lookout that it’s too foggy and he’ll have to turn back. Geoff radios him to stay afloat for a little while until it clears, but Joe wants to get back to take Bonnie to dinner, so he attempts a landing and crashes in the process, dying.
Bonnie is devastated that Joe lost his life trying to get back to her, but she’s even more upset that none of the other guys seem sad about it. She confronts Geoff, who tells her that they can’t afford to have feelings. They’re torn up inside, but if they let it out, they couldn’t go on. She joins them in their evening of drinking, and falls head over heels for Geoff. When the fog clears, he takes the run Joe would have made, and she misses her boat so she can see him land safely again.
He’s not all that thrilled to see her when he gets back, and she feels like an idiot for throwing herself at him. She vows to stay out of his way, and she does, until an old girlfriend in the form of Rita Hayworth wanders in.
This movie is full of great romantic tension as well as some amazing special effects I wouldn’t have thought possible in 1939. The air shots were quite good and I found myself swept up in this unrated drama, which, by the way, was Rita Hayworth’s first large-ish part in a film.