Yes, there are melodramatic moments...
...the woman going to pieces on the plane, and Jerry Paris slapping her across the face and telling her to "pull yourself together," the abysmal performance of Linda Darnell, the too-cute little boy...
BUT...
"Zero Hour!" has got to be one of the most suspenseful and entertaining of films. I saw it when it first came out in 1957. I enjoyed it then, and I enjoy it now. Those were the days when films had a beginning, a middle, and an ending. There was not one trace of blood, or the sight of somebody being disemboweled or being devoured by vampires.
I am an old man, incurably square, and incurably sentimental. I long for "the good ole days" of films like "Zero Hour!"
"First the worst. Second the same. Last the best of all the game."