'I checked the dates in old newspapers. I found out that the pearl vanished exactly two days before Beppo was arrested for attacking someone. And this attack happened in the factory of Gelder & Co., at the very moment when the busts of Napoleon were being made. Now you can clearly see how things happened, though of course when I started the case, I saw the last things first. Beppo had the pearl. He may have stolen it from Pietro, he may have stolen it with Pietro, or he may have been taking it from Pietro to his sister. It is of no consequence to us which answer is the correct one.

The important thing is that Beppo had the pearl. And at the time he had it with him, he was being chased by the police. He went to the factory where he worked. He knew that he had only a few minutes to hide this enormously valuable pearl. Otherwise the police would find it on him when he was searched. Six plaster casts of Napoleon were drying in the hallway. One of them was still soft. In a second Beppo, who was a skilful workman, made a small hole in the wet plaster. He dropped in the pearl, and with a few touches covered over the hole he had made. It was an admirable hiding-place. No one could possibly find it.

But Beppo was punished for his attack with a year in prison, and meanwhile his six busts were scattered over London. He could not tell which one his treasure was in. He could only see by breaking the busts. Even shaking would tell him nothing, because the plaster was wet so the pearl would probably stick to it - as, in fact, it has done. Beppo did not despair, and he carried on searching. He was clever and he did not give up.