The giant king squid lives in the deep sea. There are legends of sirens in the seafaring civilizations of many countries, and they all look very similar to squid. Modern people also have some fragmented knowledge of the king squid.

Some seafarers on night watch at sea once saw the squid's 20-meter-long tentacles sweeping across the deck, and those objects that could be caught were swept out to sea, and the next day, people found iron barrels hanging on the side of the ship with several rows of teeth gnawing through them.

During the Second World War, the U.S. Navy, a destroyer weighing thousands of tons in the night voyage suddenly found that the speed slowed down, but could not find any faults, when people sent it into the dockyard for repairs, only to find that its propellers have been bitten by sharp teeth through dozens of holes.