Hollywood itself could hardly have scripted a better battle. According to eyewitnesses, a German U-boat lurking off the shores of North Point, Prince Edward Island, laid a trap for an unsuspecting convoy transitting the Northumberland Strait. On 7 May 1943, the trap was sprung, Canadian naval escorts and aircraft did their best to defend the beleaguered convoy from a brazen and unorthodox attack that was unlike any other. There could only be one conclusion: the German commander was half-mad. Just like the fictional Captain Ahab, he was willing to take unwarranted risks with his boat and men to destroy his white whale that came in the form of a troop ship at the centre of the convoy. His obsession led to a stunning three hour engagement that was brought to a dramatic end as the Canadians scored a direct hit forcing the U-boat’s bow to rise sharply out of the water before sinking. The problem is that there is no evidence that this battle ever took place.
Mayne, Richard O. "The Great Naval Battle of North Point: Myth or Reality?." Canadian Military History 16, 3 (2007)