Parents Guide for
The Man Who Knew Too Much (1956) More at IMDbPro »

There's a little violence, spread out throughout the film. There's a stabbing with a little blood shown, as well a scene near the end which resolves around the assassination of a British Politician.

The plot of the film can be quite frightening once the plot advances from a spy story to that of a kidnapping and assassination conspiracy. The Master of Suspense lives up to his name in the ending finale.