Tintin ha Milik a syw kevres a olyow koynt neb a’s hembronk war hyns bagas peryllus a noswikoryon koskles.  Orth aga helghya, Tintin yw prisonys yn karg gorhel Kapten Hernenn, an Karaboudjan, le mayth usi an kapten yn-dann dhelanwes alkohol ha maystrys gans y vayni vil. A-dhiworth downderyow an Mor Kres dhe doemmder difeythtir an Sahara, an aneth ma a worr Tintin ha’y gowetha yn trobel euthyk.

Tintin and Milik follow a series of strange clues which lead them on the trail of a dangerous gang of drug smugglers. In their pursuit, Tinitin is locked up in the brig of Kapten Hernenn’s ship, the Karaboudjan, where the captain is under the influence of the bottle and under the thumb of his dastardly crew. With the scorching Sahara desert at one hand and the depths of the Mediterranean on the other, this adventure places Tintin and his friends in some dangerously dire straits.