“Well, Watson, what do you make of this?” asked Holmes, after a long pause.

“It is an amazing coincidence.”

“A coincidence!  Here is one of the three men whom we had named as possible actors in this drama, and he meets a violent death during the very hours when we know that that drama was being enacted.  The odds are enormous against its being coincidence.  No figures could express them.  No, my dear Watson, the two events are connected—­must be connected.  It is for us to find the connection.”

“But now the official police must know all.”

“Not at all.  They know all they see at Godolphin Street.  They know—­and shall know—­nothing of Whitehall Terrace.  Only we know of both events, and can trace the relation between them.  There is one obvious point which would, in any case, have turned my suspicions against Lucas.  Godolphin Street, Westminster, is only a few minutes’ walk from Whitehall Terrace.  The other secret agents whom I have named live in the extreme West End.  It was easier, therefore, for Lucas than for the others to establish a connection or receive a message from the European Secretary’s household—­a small thing, and yet where events are compressed into a few hours it may prove essential.  Halloa! what have we here?”

Mrs. Hudson had appeared with a lady’s card upon her salver.  Holmes glanced at it, raised his eyebrows, and handed it over to me.

“Ask Lady Hilda Trelawney Hope if she will be kind enough to step up,” said he.

A moment later our modest apartment, already so distinguished that morning, was further honoured by the entrance of the most lovely woman in London.  I had often heard of the beauty of the youngest daughter of the Duke of Belminster, but no description of it, and no contemplation of colourless photographs, had prepared me for the subtle, delicate charm and the beautiful colouring of that exquisite head.  And yet as we saw it that autumn morning, it was not its beauty which would be the first thing to impress the observer.  The cheek was lovely but it was paled with emotion, the eyes were bright but it was the brightness of fever, the sensitive mouth was tight and drawn in an effort after self-command.  Terror—­not beauty—­was what sprang first to the eye as our fair visitor stood framed for an instant in the open door.

“Has my husband been here, Mr. Holmes?”

“Yes, madam, he has been here.”

“Mr. Holmes.  I implore you not to tell him that I came here.”  Holmes bowed coldly, and motioned the lady to a chair.

“Your ladyship places me in a very delicate position.  I beg that you will sit down and tell me what you desire, but I fear that I cannot make any unconditional promise.”