The Secret of the Unicorn: Part 1 - S1-E3
Other mistake: When Tintin attempts to break down Captain Haddock's door, there is no key lock hole on the front of the door, but there is a key lock hole on the back of the door. (00:10:50)
The Secret of the Unicorn: Part 1 - S1-E3
Audio problem: When Captain Haddock's neighbour says "Is everything all right?" her mouth is wide open but doesn't move. (00:10:55)
The Secret of the Unicorn: Part 1 - S1-E3
Continuity mistake: When Captain Haddock shows Tintin the journal that belonged to Sir Francis Haddock, it's brown. Much later on in the episode, after Haddock has finished telling Tintin about the story of Francis Haddock, the journal is suddenly much lighter. (00:11:40 - 00:19:45)
The Secret of the Unicorn: Part 1 - S1-E3
Other mistake: When Haddock stabs the cushion on the couch, the sword goes right through the cushion, but no damage is made to the couch. (00:15:25)
The Secret of the Unicorn: Part 1 - S1-E3
Continuity mistake: When the pirates are partying, one of them throws a wine bottle towards the tied up Francis Haddock. One of his hands is shown tied and wrapped in ropes. The shot then switches to a close-up of his hand, which is now wrapped around the ropes tying his body to the mast, and not the other ropes shown a second ago. (00:17:10)
The Secret of the Unicorn: Part 1 - S1-E3
Deliberate mistake: After Francis Haddock kills Red Rackham, he lights a fuse to the explosives. The fuse that was lit is only a foot long, yet he is somehow able to climb out the ship without anyone noticing, get into a boat and swim all the way to land before it explodes. At a foot long it would have exploded in 10 - 15 seconds, all of that would taken at least 10 minutes. (00:18:45)
The Secret of the Unicorn: Part 1 - S1-E3
Revealing mistake: Francis Haddock lowers himself from the ropes to the lifeboat below. He steps foot inside the boat, but the bottom of his legs and his feet are still perfectly visible when they should have been covered up by the boat. This error in the animation makes the boat appear as if the boat is missing one of its sides. (00:18:50)
Chosen answer: It is a pill that makes alcohol taste disgusting.