Continuity mistake: When Tintin phones the operator to connect him to the police, she is holding a green wire. Then when the Mafia member takes it off her the wire is now blue. (00:07:05)
Destination Moon: Part 2 - S3-E10
Continuity mistake: When Calculus is driving himself, Tintin and Haddock out of the base, Calculus drives down a hill and back onto the main road. Haddock is still sitting in his seat, but in the next shot, he is suddenly standing up. (00:30:15)
The Seven Crystal Balls: Part 1 - S3-E3
Character mistake: When Sanders is finishing the translation, the last sentence that he writes down is "Over the mountains and beyond the sea", but the sentence shown on the paper is "les mois et les monts"; this is French for "The months and the mountains." The real translation for "Over the mountains and beyond the sea" is "Sur les montagnes et au-delĂ de la mer." Even if the translation is carrying on from the previous line, a majority of the final sentence would still be incorrect in the translation. (00:02:25)
Explorers on the Moon: Part 1 - S3-E11
Audio problem: Captain Haddock's mouth doesn't move when he says "Relax? Relax?!" just after Calculus says they have to start the calculations.
Answer: According to Wikipedia, he is described as being a youth anywhere from 14 - 19 years old. There is no specific age.
raywest ★