While you, and Rosie were waiting for your order, the man in the trench coat from the auction sneaks away, takes the stairs, down to the lowest part of the ship. As the man avoided the kitchen, he found a door that was labeled, "For Ship Employee's Only Auction Customers Not Allowed", and went inside anyway.
As the trench coat man was now inside, he found all the treasures, the owner, and employees were selling off. Most of them were good, but what really intrigued the man, was the shiny shell covered in ruby crystals. Temping to steal the thing, the trench coat man removed the glass case it was around, and grabbed the shell, while swapping it with a bag of pebbles. Once the swap was finished, the trench coat man placed the glass case over the pebble bag, and then left the room, taking the shell with him.
Unfortunately, the man wasn't so lucky, as the glass case fell off, and shattered, causing an alarm in the room to blair out. That was when, magic dust surrounded the room, that the trench coat man was in.