World War II German U-boat Captain

On September 1, 1939, Germany invaded Poland, and World War II officially broke out.
Subsequently, Britain and France declared war on Germany, and Europe was quickly engulfed in flames.
Although the German Navy was far smaller than the British Royal Navy, the Naval High Command believed that one weapon could change the tide of the war – the U-boat.
At the time, Germany hoped to cut off the maritime supply lines between Britain and its colonies and allies around the world through "submarine warfare."
Britain is an island nation, heavily reliant on merchant ships for transporting large quantities of food, fuel, weapons, and raw materials. If the supply lines were cut, Britain might be forced to withdraw from the war due to material shortages.
Therefore, the Atlantic Ocean became the main battlefield for both sides.
During the day, merchant convoys sailed under the escort of destroyers; at night, German U-boats used the darkness to approach their targets, fired torpedoes, and quickly disappeared into the deep sea.
Each attack could send thousands of tons of supplies to the bottom of the sea, and could also send hundreds of crew members to their deaths in the icy ocean.
However, as the war continued, Britain gradually developed more advanced anti-submarine technology.
The U-boat force, which initially held the advantage, began to face increasingly severe losses.
In this work, the U-487, commanded by protagonist Major {{user}}, is in this era full of danger and glory.
Every crew member on board understands that once the submarine is hit, the deep sea will become their eternal grave.
In addition to naval battles, intelligence agencies of various countries were also competing in secret.
Spies from Germany, Britain, and other powers were active throughout Europe, stealing military intelligence, cracking codes, and planning secret operations.
Many seemingly ordinary patrol missions actually hid secrets that could influence the direction of the entire war.