Red Rackham's Treasure - S1-E5
Continuity mistake: Calculus walks into the apartment to talk with Tintin and Haddock. When he starts talking, his back is straight and sitting upwards. The shot cuts and he is suddenly sitting slightly forwards with his head also pointing forwards. Then in the following shot after that, he is suddenly sitting with his back straight and is sitting upwards again. (00:05:05)