Acting for Two: Thomson and Thompson are played by the same actor (Charles Kay) in the BBC radio adaptations.
Adaptation First: Portugal was the first country to do the following:
Having Tintin translated into a language other than French;
Having Tintin published in color (from the get-go). Hergé reportedly liked it;
In Tintin in the Congo (which was published as Tintin in Angola), replacing Tintin's school lesson about Belgium with a math lesson where he writes "1+1=2" (also from the get-go).
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 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 occupiers 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.
Cash-Cow Franchise: Despite not having any new adventure since Hergé's passing, the series consistently remains among the best-selling Franco-Belgian Comics. Collectible figures are still a hot commodity, and for the past 20 years or so the GEO magazine isn't done selling magazines and anthology books with Real Life / comic book page comparisons to highlight all the quasi-ethnological and geographical research (or lack thereof sometimes) Hergé did.
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 (Belgium was under Nazi occupation at the time).
Creator Breakdown: Hergé had one over Tintin in Tibet, though it ended up being one of his best stories anyway. See the Heartwarming page.
Cross-Dressing Voices: Most dubs of the animated series have Bianca Castafiore voiced by a man.
Deleted Scene: A number of panels or even pages were removed from later printings, sometimes because of a change in format, the author deciding they weren't needed, or political context (such as a conflict pitting Jews against Arabs in a British protectorate).
Died During Production: 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.
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 Shown Their Work 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.
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.
Science Imitates Art: Asteroid 1683 Castafiore is named for diva Bianca Castafiore.
Science Marches On: Destination Moon and Explorers on the Moon, written a decade before the Apollo moon landings, shows this. For instance, water ice is shown to exist on the surface of the moon, which is also very craggy as opposed to being flat like real life.
Hergé was working on the early stages of a Grand Finale for the Tintin series, "Tintin and Alph-Art," when he unexpectedly died.
Flight 714 was apparently just going to be a Slice of Life story that takes place inside an airport lobby.
Hergé considered sending Tintin to some place like the Yukon or Greenland once. Nothing came of this.
In 1948, Hergé wrote to Walt Disney hoping to pitch his series into a potential animated feature in an effort to introduce Tintin to American audiences. The proposal fell through as Disney was busy working on Cinderella around that time, though Hergé did receive a Mickey Mouse trophy and a picture showing Tintin and Mickey shaking hands decades later.
Word of God: Hergé told in an interview that Tintin and Haddock's Dreadful Musician opinion of Bianca Castafiore's singing is supposed to be their own opinion and she's actually a good singer (since she is a world famous opera singer).
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 and walking sticks.
were removed from later printings, sometimes because of a change in format, the author deciding they weren't needed, or political context (such as a conflict pitting Jews against Arabs in a British protectorate).