Tintin/Recap/Red Rackham's Treasure

Red Rackham's Treasure (1944) is the 12th adventure of Tintin and a direct sequel to The Secret of the Unicorn. In the previous tale Tintin and Captain Haddock had discovered three parchments revealing the location of the Unicorn, a sunken ship. Said ship contains the treasure of famed pirate Red Rackham. In this adventure, the two friends set out on a naval expedition to locate the treasure. Accompanying them are Thomson and Thompson, determined to protect them from rival treasure hunters.

The small group is joined by a stoweaway, Professor Cathbert Calculus. He is an inventor who insists that his one-man submarine is ideal for the for this mission. The Professor himself turns out to be very useful in locating the ship, as the centuries-old co-ordinates are less straightforward than originally thought. Calculus would become the last major addition to the cast of the series. The album is considered one of the highlights in the series and 'served as a change of direction for the protagonists. As Haddock becomes independently wealthy in the process.

Tropes

 * Breakout Character: Professor Calulus. Hergé had been using various Absent Minded Professors as characters in previous stories. All were one-shot characters. But Calculus went on to become a recurring character, and Destination Moon, Explorers on the Moon and The Calculus Affair all centered around his achievements.
 * Deserted Island: One figures prominently in the plot. Francis Haddock had once landed on the isle. Tintin and his crew find the island long deserted by humans and filled with the skulls of its former inhabitants. A large population of parrots keeps repeating the words of the 17th century visitor. At first the protagonists think this is a Treasure Island. But soon realize that nobody would hide his treasure in an island and never return to it.
 * Gadgeteer Genius: Professor Cathbert Calculus and his specialized submarine.
 * Nothing Is the Same Anymore: From this story onward, Haddock and Calculus live a life of luxury in Marlinspike Hall, with most stories beginning or at least taking place partially there. Although Tintin himself doesn't move into Marlinspike Hall, we almost never see his old apartment in any of the following adventures.
 * Pirate Booty: The title already indicates that the story is about the treasure of a pirate. Red Rackham and his pirates were introduced in the The Secret of the Unicorn.
 * Ship Shape Shipwreck: Averted. The wreck of the Unicorn has decayed considerably.
 * Treasure Map: Averted. While this is a treasure hunt story, the co-ordinates of the sunken ship are not part of a map. They are written on three parchments and have to be deciphered. The protagonists originally thought that the Sir Francis Haddock calculated them based on the Greenwich Meridian. Calculus correctly figures that the French naval officers under louis XIV were using the Paris Meridian as their reference point.
 * What Happened to the Mouse?: Max Bird, the villain of the previous story, is mentioned to have escaped from prison. Thomson and Thompson suspect that the man is seeking revenge and could be hiding aboard the treasure-hunter's ship. That convinces the two officers to volunteer their services in this journey. In the end, this plot point seemingly just serves as an excuse to get Thomson and Thompson into the story. By the time the story concludes, there is nothing to indicate that Max was ever aboard the ship. Or even near it. The Thom(p)sons claim he was "discouraged by their presence". Max never appears in any later stories, either. His fate is never resolved.