Le secret de la Licorne (1994)

Whilst browsing in a market in Brussels, Tintin purchases an old model ship which he wishes to give to his friend Captain Haddock as a gift. Two strangers, the model ship collector Ivan Ivanovitch Sakharine and a mysterious figure known as Barnaby, then unsuccessfully try to independently convince Tintin to sell the model to them. Returning with the model to his flat, Snowy knocks it over and its mainmast is broken. Repairing it, and showing the ship to Haddock, the latter is amazed that it is actually a model of the Unicorn, a 17th-century warship captained by his ancestor, Sir Francis Haddock. The model ship is subsequently stolen, and it is revealed that Sakharine owns an identical model of the Unicorn, although this is also soon stolen. Returning to his flat, Tintin discovers a rolled-up parchment hidden under furniture, on which is a part of a riddle that points to the location of treasure, and he realises that this must have been hidden in the mast of the model which Snowy had broken.

Informing Haddock about the riddle, the captain tells him of how Sir Francis Haddock battled with the pirate Red Rackham somewhere in the West Indies, before killing him in single combat and blowing up his ship. Haddock gets somewhat carried away in his telling of the story: destroying his flat while re-enacting the battle scenes.

Barnaby then turns up at Tintin's doorstep but is shot down by unknown assailants. Later Tintin is kidnapped by the perpetrators of the shooting. They are revealed to be the Bird brothers, two unscrupulous antique dealers who own a third model of the Unicorn. They are behind the theft of Tintin's model and Sakharine's parchment, knowing that only with all three parchments can the location of the treasure be found for the following book Red Rackham's treasure.
Tintin escapes from the Bird brothers' country estate, Marlinspike Hall, whilst the Captain arrives with the police officers Thompson and Thomson to arrest them. However, it is found that they do not have two of the parchments. These are found to have been stolen by Aristides Silk, a kleptomaniac specialising in wallet-snatching. As the pickpocket is cornered, his cache of stolen wallets is found, amongst which are the Bird Brothers' wallets containing the missing two parchments. By combining the three parchments, Tintin and Haddock discover the coordinates of the hidden treasure, and begin to plan for an expedition to find it. The story ends where it started, leading Tintin to the rest of the treasure.