A German submarine underway off the Canadian coast near the Saint Lawrence River in North America, during World War 2. A map shows the area of interest. The German submarine underway on the surface in calm waters. Crew members play cards below decks of the U-boat. A sailor cooks food. Others eat the food. The submarine submerges and the Canadian coast is scanned through a periscope. Torpedoes are fired and an oil tanker is hit. The oil tanker burns. Black smoke arises as the tanker burns.