"Half a minute, Sinclair," I said, "who did you say was under the Dog's thumb?"

"Demonio."

"Thanks. I was mixed in the thumbs. Go on."

"Well, just when things are like this...."

"Like what?"

"Like I said."

"All right."

"Who should turn up and thwart the whole scheme, but this Signorina Tarara in her domino...."

"Hully Gee!" I said, "you make my head ache. What the deuce does she come in her domino for?"

"Why, to thwart it."