Nick drew a long breath and set his lips together firmly.  He had felt that something was wrong in that house.  The waiter who had run across the sidewalk and got into that carriage had borne a guilty secret with him, as the detective’s experienced eye had instantly perceived.

But this was a good deal worse than Nick had expected.  He had looked for a robbery, or, perhaps, a secret and bloody quarrel between two of the waiters, but not for a murder such as this.

One glance at the woman showed her to be elegant in dress and of a refined appearance.

She could have had nothing in common with the missing Corbut, unless, indeed, he was other than he seemed.

Certainly, whatever was Corbut’s connection with the crime, there was another person, at least, as intimately concerned in it.  And he, too, had fled.

Where was the man who had brought this woman to this house?  How was it possible to account for his absence except by the conclusion that he was the murderer?

That was the first and most natural explanation.  Whether it was the true one or not, the man must be found.

Nick turned to Gaspard.  The head waiter had sunk down on a chair by the table and seemed prostrated.

From previous experience Nick knew Gaspard to be a man without nerve, and he was not surprised to find him prostrated by this sudden shock.

There was a bottle of champagne standing in ice beside the table.  The detective opened it and made Gaspard drink a glass of the sparkling liquor.

It put a little heart into the man, and he was able to answer questions.

Nick, meanwhile, closed the door of the room.  Apparently the tragedy was known only to Gaspard and himself and to the guilty authors of it.

“Did you see this woman when she came in?” asked Nick.

“No.”

“Who showed her and the man with her to this room?”

“Corbut.”

“Who waited on them?”

“Corbut.”

“Who waited on the people in room A?”

“Corbut.”

“They are gone, I suppose?”

“Yes; I looked in there before I came in here.”

“Did you see any of these people?”

“I saw the two men.”

“How did that happen?”

“One of them came out into the hall to call Corbut, who had not answered the bell quick enough.”

“Which one was that?”

“The man in room A.”

“How do you know?”

“Because I saw the other man, later, coming out of room B.”

“This room?”

“Yes.”

“You are sure of that?”

“Perfectly.”

“Did he see you?"’

“I think not.  I was standing right at the corner of the two halls.  The man came out and glanced around, but I stepped back quickly, because we do not like to appear to spy upon our guests.  He did not see me.”

“What did he do?”