Cigars of the Pharaoh: Part 2 - S1-E7
Continuity mistake: When Tintin and the doctor walk through the corridor to the room, the door to the room is white and the window on the door is closed. In the next shot, the door is a yellow/beige color and the window on the door is now open. The window is then closed after the doctor locks Tintin in the room. (00:33:30)