It is true that the description of this man tallies with your idea of the second party in this mystery. But why should he come back to the house after leaving it? That is not the way of criminals.”
“The ring, man, the ring: that was what he came back for. If we have no other way of catching him, we can always bait our line with the ring. I shall have him, Doctor—I’ll lay you two to one that I have him.

Chapter 4