I'm not sure how many of you are aware of this. I'm quite a hardcore Tintin fan but only became aware of this a few months ago when a friend told me about it, and I was thrilled by the discovery and all the Tintin images I was seeing for the first time.
I quote straight from the source:
In 1958, Hergé asked the famous Belgian creator of comic strips, Greg (Michél Regnier) to make a synopsis for a possible story with Tintin. Greg presented two ideas, Les Pilules and Le Thermozéro. These were two parallell files, one that developed the story and another concentrating on possible gags, as Greg was well aware of the fact that Hergé wanted to develop those himself.
Read on and see the images ...
Tintin and Haddock are out driving in a car. Outside a service station, Haddock argues with a large man (who happens to belong to a secret organization). Soon afterwards, the large man overturns our friends with his Volkswagen Beetle, but he loses control over the car and crashes in a tree.
Tintin and Haddock helps the injured man and some other persons turn up; Jolyon Wagg and his family, an American from Dallas named Larry (or Harry) Larmon and two mysterious, german-speaking men. When the injured man spots them, he gets scared and hides something in his pocket. The storyline would have taken Tintin to the heart of Berlin, but Hergé interrupted this project at the end of 1960 after having sketched eight pages, preferring to maintain complete control over his work. In 1959, the production company Belvision started to produce seven animated Tintin-films for television, adapted by Greg. Fairly successful, this series convinced Belvision to produce two films for the cinema. In 1969, Greg adapted The Seven Crystal Balls and The Prisoners of the Sun into one film. In 1972 came the second animated Tintin movie, Tintin and the Lake of Sharks. To avoid the problems with the adaption of an existing album, this film was an original story of Greg's. In addition to this, Greg was also Editor-in-Chief of Tintin magazine from 1964 to 1973.If you have any more information about this than what mentioned in the source, please leave a comment. btw I like the margin art on those pages even more than the strips ... it just shows what a brilliant artist Herge was.