Intrepid young reporter, Tintin, and his loyal dog, Snowy, are thrust into a world of high adventure when they discover a ship carrying an explosive secret. As Tintin is drawn into a centuries-old mystery, Ivan Ivanovitch Sakharine suspects him of stealing a priceless treasure. Tintin and Snowy, with the help of salty, cantankerous Captain Haddock and bumbling detectives, Thompson and Thomson, travel half the world, one step ahead of their enemies, as Tintin endeavors to find the Unicorn, a sunken ship that may hold a vast fortune, but also an ancient curse.

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.

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.

Tintin and Captain Haddock travel to Peru in search of an abducted friend.