"Lord Wisbeach thought that they were trying to steal my nephew's explosive. Perhaps you have read in the papers that my nephew, Willie Partridge, has completed an explosive which is more powerful than any at present known. His father—you have heard of him, of course—Dwight Partridge."
Mr. Sturgis nodded.
"His father was working on it at the time of his death, and Willie has gone on with his experiments where he left off. To-day at lunch he showed us a test-tube full of the explosive. He put it in my husband's safe in the library. Lord Wisbeach is convinced that these scoundrels are trying to steal this, but I cannot help feeling that this is another of those attempts to kidnap my son Ogden. What do you think?"
"It is impossible to say at this stage of the proceedings. All we can tell is that there is some plot going on. You refused, of course, to allow Mitchell to come back to the house?"
"Yes. You think that was wise?"
"Undoubtedly. If his absence did not handicap them, they would not be so anxious to have him on the spot."
"What shall we do?"
"You wish me to undertake the case?"
"Of course."
Mr. Sturgis frowned thoughtfully.