How Does Mr. Wong Get Hold of the Gem?
***SPOILER ALERT!***
By the end of the story, the gem is in Mr. Wong's possession. Maybe I missed something, but it's not clear to me how he came by it. As far as I can tell, the gem had been taken earlier from the murdered man's safe (presumably by the murderer, though we are never told how the murderer -- or anyone else -- came by the combination or the key to the safe), and we have not seen the gem in anyone's possession since it went missing.
The only possibility I can think of is that in the final scene, when Mr. Wong shakes hands with the murderer, the murderer (who clearly has something clenched in his hand that he wishes to transfer to Mr. Wong during during the handshake) gives the gem back to Mr. Wong. This would make sense, given that the gem was never an object of desire for the murderer in the first place, so it is no skin off his nose if the gem goes back to China via Mr. Wong. However, when we see Mr. Wong open his hand after the transfer -- and the camera focuses on his hand, as if to say, "Hey, viewer, take note of what's in Mr. Wong's hand," no gem is there, but only what looks like a combination of brown flecks of pocket debris and little white beads or pills. So when the gem shows up in Mr. Wong's hand 2 minutes later, we are left scratching our heads; when did he obtain it, and how?
A connected question is this: What are the little white beads or grains that the murderer passes on to Wong? Are they little poison pills -- perhaps what was used to poison the cigarettes? If so, what was the point in giving them to Wong? Surely not to harm him, since they have their effect only when smoked, and Wong, who has discovered the secret of the cigarettes, would not be so stupid as to insert them into a cigarette and smoke them.
I wonder if a major editing or scripting error didn't occur here. I wonder if there were originally two slightly different endings, one in which the handshake transfers the gem to Wong, and the other in which the handshake transfers the little white things, and if in the final edit of the film, the editor forgot that the little white things (whatever they were supposed to be) were no longer important to the plot, whereas giving the gem to Wong was.
Does anyone have any thoughts on this? (Note: It would be best to put a "Spoiler Alert" warning above any answer, so as not to reveal too much about the ending to those who haven't seen the film.)