This moment is the aforementioned Hitchcock technique embodied. 

In 1941 France, S.S. Colonel Hans Landa arrives at his farm looking for the Dreyfus family. If he finds them, he will kill them. We know that if the farmer, Perrier LaPadite, is found harboring this Jewish family, Landa will likely murder him and his family too. The camera lowers underneath the floorboards where we see the Dreyfus family, covering their mouths and noses to keep from being heard. 

The suspense comes from KNOWING the family is hiding there and KNOWING what will happen if they are discovered. If we didn’t have that information, the scene would have no tension.