Nobody appears to know anything about him.

I remember when he was staying here before that he had no callers, and seemed to spend most of his time sitting in the palm court." The inspector nodded.
"He was certainly a man who knew how to keep his own counsel," he admitted.

"Most Americans are ready enough to talk about themselves and their affairs, even to comparative strangers." The hotel clerk nodded.
"Makes it difficult for you," he remarked.
"It makes the case very interesting," the inspector declared, "especially when we find him engaged to lunch with a young lady of such remarkable discretion as Miss Penelope Morse." "You know her ?" the clerk asked a little eagerly.
The inspector was engaged, apparently, in studying the pattern of the carpet.
"Not exactly," he answered.

"No, I have no absolute knowledge of Miss Penelope Morse.

By the bye, that was rather an interesting address that she gave." "Devenham House," the hotel clerk remarked.