Continuity mistake: When Tintin and the others are locked in the room, Tintin looks out the window, assuming he thought he heard Snowy. On the left hand side of the window is a plant. A few minutes later, Snowy arrives and the plant is still there, but when Tintin throws Snowy out the window telling him to wait, the plant has vanished. (00:13:55 - 00:16:20)
Continuity mistake: Captain Haddock places three strips of tape over Rastapopoulos', Carreidas' and Krollspell's mouths. The last piece of tape over Rastapopoulos' mouth is a strip that goes from the top of his left cheek down to the bottom of his right cheek. A few seconds later, as they leave the room and go outside, it goes from the top of his right cheek down to the bottom of his left cheek. (00:20:35)
Continuity mistake: At the start, keep an eye on the tape strips over Carreidas' mouth. There is a vertical piece of tape directly over Carreidas' mouth, followed by another piece of tape from the top of his right cheek down to the bottom of his left cheek positioned at a sideways angle, followed by another piece of tape from the top of his left cheek down to the bottom of his right cheek also at a sideways angle. All three strips of tape are meeting with each other at a midway point by his mouth. However, when Haddock says "Come on" to Carreidas and Krollspell when they are under fire later on, the tape strips positioned sideways now meet each other at around Carreidas' left cheek area, further away from his mouth. (00:25:45 - 00:26:40)
Continuity mistake: When Allan realises that Rastapopoulos wants Carreidas alive, there is a grenade pin in one of his fingers from the grenade that he just took out. Allan then throws the grenade away, and the pin for the grenade has suddenly vanished. (00:28:55)
Continuity mistake: When the group is reunited with Gino and Skut, Skut is smiling with his mouth open. Tintin walks over to them in the next shot, and Skut's mouth is suddenly closed. (00:33:30)
Chosen answer: It is a pill that makes alcohol taste disgusting.