Unexpected ending, typical Roald Dahl

Landlady is a short story written by a British novelist Roald Dahl. As you may know, Roald Dahl is known for ending his stories unexpectedly, like the short story Landlady.
         Billy is a young man who traveled to a little town in England, and tried to find a place he could stay at while he was on his business trip. After searching for a perfect place to stay at, he finally saw a place that literally caught his eyes. Everything looked normal; a dog was lying on the carpet and the parrot was sitting in its cage. He went up and knocked on the door and the old women opened it immediately. She was extremely happy to see Billy, and that’s when I thought that the story may have an unexpected ending.
                  When Billy found out that there were some other visitors in the third floor, he started to figure out that something is really wrong, he wanted to see them with his own eyes. The lady didn't cause any resistance and as they were done with drinking the tea, the old lady looked at Billy and somehow she turned him in to some type of doll, he couldn't move or speak. He was paralyzed. It turned out that the animals Billy saw in the window were dead, or they were stuffed by the lady after they died. I think that those others visitors also had been paralyzed just like Billy.