"You think, then, that she is really in danger?" Mrs. Morton gasped.
"I do not wish to alarm you, but I very much fear that she is."
"But I don't know any private detectives," Mrs. Morton began.
Stapleton looked up from the letter.
"When I spoke," he said, "I had a certain man in mind. He is not a detective, in the usual sense of the word. You can find plenty of those, of course, but, while they are useful enough in the detection of criminals of the ordinary sort, they would probably have very little success in an affair such as this. The man I had in mind is a brilliant criminal investigator, one whose services I have more than once been obliged to make use of in matters of a personal nature. Some two years ago, for instance, my child was kidnapped, in Paris, and held for ransom. The entire police force of the French capital seemed powerless to discover his whereabouts. At last I called in Richard Duvall, and within a few days my boy was returned to me, and the criminals who had abducted him placed under arrest. It was a marvellous, a brilliant piece of work. I am not likely to forget very soon the mystery of the changing lights." He paused, and Mrs. Morton spoke up eagerly.
"Give me Mr. Duvall's address," she said, "and I will see him at once."
"That," Mr. Stapleton smiled, "is, of course, the great difficulty. Duvall, who is married, lives with his wife on their farm near Washington. They both have plenty of money, and he has practically retired from professional work."
"Then of what use is it to suggest his name?" asked Mrs. Morton, quickly.
"He had already retired," Stapleton rejoined, "at the time of my boy's kidnapping, but I prevailed on him to take up the case. His retirement merely means that he is not in the active practice of his profession. But exceptional cases, cases which by reason of their novelty interest him, he may be persuaded to undertake. I fancy this matter of your daughter's would prove attractive to him. It is unusual—bizarre. I strongly advise you to see him."
"To do that, I must go to Washington?"