The Story of Thessalonike
There exists a popular Greek legend which talks about a mysterious mermaid who lived in the Aegean Sea.
She was thought to be Thessalonike, sister of Alexander the Great.
The legend states that Alexander, in his quest for the Fountain of Immortality, retrieved with great exertion a flask of immortal water with which he bathed his sister’s hair. When Alexander died, his grief-stricken sister attempted to end her life by jumping into the sea.
Instead of drowning, however, she became a mermaid - passing judgment on mariners throughout the centuries and across the seven seas. To the sailors who encountered her she would always pose the same question: “Is Alexander the king alive?” to which the correct answer would be “He lives and still rules”.
Given this answer she would allow the ship and her crew to sail safely away in calm seas. Any other answer would transform her into a raging Gorgon, bent on sending the ship and every sailor on board to the bottom.