Actor Allusion: Of sorts. Professor Calculus' look is based on Professor Auguste Piccard, famous physicist and balloonist at the University of Brussels. When Bianca Castafiore is introduced to Calculus she mistakes him for a famous balloonist.
Ascended Fanon: The version of Tintin and Alph-Art by fan artist Yves Rodier almost became this, as Herge's former assistant Bob de Moor attempted to have it released as an official entry in the series. However, de Moor himself died before this could be done, and nothing came of it.
Author Existence Failure: Hergé died partway through his work on Tintin and Alph-Art; the unfinished draft has been published as part of the regular series of Tintin albums.
Author Phobia: Author Hergé was forced to listen to his aunt singing opera arias when he was a child. It led to a strong dislike of opera music, exemplified in the character Bianca Castafiore, whose singing usually scares away Tintin and Haddock or makes glass break.
Surprisingly averted with Tintin in Tibet, likely because it's politically neutral. Played straight in a number of markets when publishing Tintin in the Congo, however...
Red Sea Sharks is specifically banned from importation in Egypt, and only Egypt, for political correctness issues. Both its comic and animated versions, along with those of those for L'Or Noir and Tintin in Congo were skipped as well from the Arabic dubs, although they are still available in markets in their original versions.
There were a number of historical examples too. The Black Island and Tintin in America were banned by the German occupieers of Belgium during World War II due to the perception that they were sympathetic to Britain and America, respectively. Of course, the Nazi censors were not too thorough in analyzing which books to ban, as they did not ban King Ottokar's Sceptre, which involves the hero undermining a fascist coup.
Creator Breakdown: Hergé had one over Tintin in Tibet, though it ended up being one of his best stories anyway. See the Heartwarming page.
The earliest adventures, which appear out of place when one knows the entire series, were the product of Hergé just doing what he was told by his boss at Le Petit Vingtième, the Abbé Norbert Wallez, who was quite intent on using the comic strip as propaganda. After the first adventure, Hergé wanted to send Tintin to America immediately because he really wanted to write about Indians. Abbé Wallez however insisted he first write a story that would encourage readers to emigrate to the Belgian Congo. Wallez also liked to meddle in the private lives of his employees, setting up Hergé with his secretary and officiating at their wedding!
The Black Island was completely redrawn and In the Land of Black Gold redrawn and rewritten on the insistence of Tintin's British publishers Methuen.
Follow the Leader: Virtually every European comic strip owes something to Tintin. If they are not directly inspired by it, they at least read it in their youth. The Tintin magazine was full of comic strips directly inspired by Hergé's drawing style (the so called Ligne Claire (clear line) style, characterized by all the inking lines having the same width, no hatching to suggest shadows, and an almost anal-retentive level of emphasis on Showing Your Research and detailed backgrounds).
Franchise Zombie: author Hergé eventually got quite tired of writing Tintin's adventures.
Missing Episode: Herge co-wrote two Tintin plays: The Mystery of the Blue Diamond (1941) and The Disappearance of Mr. Boullock. Sadly the scripts to both have since been lost.
Tintin in the Land of the Soviets and Tintin in the Congo. Soviets was pretty much ripped completely from a book about Russia at the time. Hergé regretted a lot about Tintin in the Congo, such as the animal cruelty and the artstyle. He allegedly tried to get them removed from print, but at least got to assess some of his own personal issues with Congo.
One aspect of Shooting Star Herge was allegedly not very fond of was the portrayal of the antagonists as Jewish-Americans.
The Other Darrin: In the BBC radio Productions, Haddock is voiced by Leo McKern (yes, THAT Leo McKern) in the first 6 episodes and by Lionel Jeffries for the remaining 6. Nestor changes to a new actor in the second half as well, and Castafiore changes actresses every time she appears.
Reality Subtext: The political situations in various parts of the world often loom heavily over the fictional storylines. This is especially prevalent in the books written just prior to the Second World War and the Nazi occupation.
After Hergé announced at the end of Cigars of the Pharaoh that Tintin's next adventure was to be set in China, he was introduced to Zhang Chongren, a Chinese art student living in Belgium, who offered to consult on The Blue Lotus in order to avoid the stereotypes and caricatures typical of depictions of his homeland. Hergé accepted the offer, leading to a lifetime friendship. Zhang was even included in the story and known as Chang Chong-Chen. A humorous sequence has Tintin telling Chang about European stereotypes of China, which leads him to think that the Europeans are crazy.
Hergé was particularly meticulous in his research. He kept a huge collection of photographs, newspaper articles, and anything else possibly useful in future stories, and so many places and objects in the comic books are real places. For instance, the house of Prof. Calculus' Italian friend in The Calculus Affair is a real house that is still standing to this day. Furthermore, much of the scientific information in the books is accurate, or at least was accurate for the knowledge of the time, some apparent errors being a case of Science Marches On. In a odd case to Science Marching a 180 Degree Turn, one of Hergé's most well known "mistakes" was in depicting ice on the Moon (Explorers on the Moon), but since Indian astronomers have indeed found ice there, we probably owe him an apology.
Superlative Dubbing: the European Spanish dub. Long time tintinologist Juan D'Ors adapted the scripts, directed the dub and also voiced Tintin. The result was a dub which managed to be more faithful to the original comics than the English version (for instance, dialogue was corrected so that the anachronic order of the episodes was fixed) and even slip a few references to the albums which hadn't been adapted (the opening moments of "Tintin in America" reference "Land of the Soviets" and "Tintin in the Congo" and the final moments of "Tintin and the Picaros" include a reference to the never-finished "Alph-Art").
Talking to Himself: Thomson and Thompson are played by the same actor (Charles Kay) in the BBC radio adaptations.
Hergé considered sending Tintin to some place like the Yukon or Greenland once. Nothing came of this.
Write Who You Know: For The Blue Lotus Hergé created a young Chinese boy Chang Chong-Chen (Zhang Zhongren in modern pinyin) inspired by his real-life friend Chang Chong-jen (Zhang Chongren) who he consulted on Chinese language and culture for the story. Chang also appears in Tintin in Tibet.
The Thomsons were based on Hergé's father and uncle, who were identical twins and also endeavored to dress identically — right down to the bowler hats.