While on vacation in Egypt, Tintin encounters an eccentric archaeologist who believes to have found the whereabouts of Pharaoh Kih-Oskh's tomb. There Tintin finds a cigar marked with a strange emblem.

Tintin buys an old model ship at a flea market as a gift for Captain Haddock, who tells him about the exploits of a famous ancestor related to it. Then, Tintin learns that it is not an ordinary model ship.

约尔科斯是古希腊一座美丽而繁荣的港口城市，由于波塞冬的愤怒威胁着人们，这里的生活很平静。一只年轻、爱冒险的老鼠和她收养的猫，在他们不知情的情况下，帮助老杰森和他的阿尔戈人拯救这座城市。