https://www.youtube.com/watch?v=Wqvo1O3N3nM
This is a great movie! Very entertaining!
It is about a blind detective and his guide dog, Friday. The plot involves Nazi spies trying to steal a formula, that a scientist has invented.
There is a sequence in the movie where the Nazi spies have the detective held and the blind detective is pretending that he is drunk.
The blind detective tries to prove he is sober by stating that he wants to walk a straight line, to prove he is sober and he goes through the motion of walking an imaginary, straight line! That is quite a trick for a blind man! Ha Ha Ha!