The Crab with the Golden Claws: Part 1 - S1-E1
Plot hole: Whilst Allan is searching the decks below for Tintin, a crew member is keeping watch of Captain Haddock in his quarters. Tintin secretly reveals to Haddock that he is hiding underneath his bed, without letting the crew member notice him and Haddock then looks towards him. The crew member was watching Haddock the entire time, so how does he not notice Haddock looking toward Tintin? (00:18:20)
The Crab with the Golden Claws: Part 1 - S1-E1
Plot hole: The torn off part of the Crabe Extra wrapper that Tintin discovers from the drowning victim appears completely fine, despite the fact that in the previous scene, Daws, the drowning victim, had scrunched up the wrapper and put in his pocket and was then thrown into the river, whilst the wrapper was still in his pocket. (00:02:10 - 00:03:40)
The Black Island: Part 2 - S1-E11
Plot hole: How did Tintin know the plane on the news was Mueller's plane? The broadcast was in black and white which meant the plane could have been any color. (00:33:45)
The Blue Lotus: Part 1 - S1-E8
Plot hole: When the Chinese man who visits Tintin goes crazy from the same type of dart that was shot at Doctor Sarcophagus, he tells the guard to go to the Maharajah's son. About 9 seconds later, they are seen bringing the boy back inside. There wouldn't have been enough time for them to get all the way to the ground considering they were a floor above them a few seconds ago. (00:03:05)
Cigars of the Pharaoh: Part 2 - S1-E7
Plot hole: The doctor at the mental hospital reads the letter Doctor Finney wrote him. It read that it was Tintin who was insane and Doctor Sarcophagus who wasn't insane. However, although he totally bought it, he never even took into account that Doctor Sarcophagus was pant-less or the fact that he was dancing like an Egyptian guy, which would have been enough to prove that Sarcophagus was the insane one. (00:33:15 - 00:34:00)
Chosen answer: It is a pill that makes alcohol taste disgusting.