A German, an American and an Englishman are standing by the sea... They're talking about their military's efficiency. The American boldly claims ""Our American submarines can last a month under water without ever having to go up!"". The Englishman laughs and says ""That's nothing. Our Royal Navy submarines can last half a year under water without ever having to go up!"" Both look at the German who remains silent. Suddenly a submarine emerges before them and a man jumps out shouting: ""Heil Hitler, we need fuel!"".