Tintin and his friends travel to Khemed, a Middle East nation, to help its ruler, Emir Mohammed ben Kalish Ezab, who gets into trouble when Bab El Ehr, an arms smuggler and terrorist, rises and takes over.
Tintin finds himself involved in a mystery related to a drowned man, a can of crabmeat and a ship called Karaboudjan. After investigating the ship, Tintin discovers that the shipment of cans does not contain exactly crabmeat.
While on vacation in Egypt, Tintin encounters an eccentric archaeologist who believes to have found the whereabouts of Pharaoh Kih-Oskh's tomb. Tintin finds there a cigar marked with a strange emblem.