“But, sir-”

“Just a moment. I think you will agree that your dinner engagement must go by the board. I have told Bob Moffat that I am keeping you on business. Now listen to me. Don’t worry too much. The prints are gone, but we shall get them back. This is a family matter, and I propose to deal with it in my own way. In order that I may do so I shall require you to stay here tonight. Your old room is ready for you.”

Elliot’s face set harder still.

“No, sir-I can’t do that.”

“You propose to go back to Cadogan and tell him that the prints have gone? I tell you I’m going to deal with it in my own way, and I can guarantee-yes, guarantee-that the prints will be back in our hands before the morning.”

The two pairs of eyes met, both bright, and hard, and angry. If there was a contest of wills, there was nothing to show which way it went.

Elliot spoke first.

“You said it was a family matter. Will you explain that?”

“I am about to do so. You handed me the prints at three-thirty in my office at the works. I left at a quarter past four. During that three quarters of an hour the prints were inside an attaché case on my office table, and the room was never unoccupied. I myself left it three times. On the first occasion I was away for about five minutes. You will remember that I walked along the corridor with you, and that we met Brown, the works manager, who wanted a word with me. During that time my secretary, Albert Pearson, was in the office. When I got back I sent him to Bob Moffat with some figures which he had asked for. Shortly after that my stepson, Frank Ambrose, came in with my nephew, Mark Paradine. I was away for about a quarter of an hour whilst they were there. When I came back Frank had gone and Mark was just leaving. Lastly, my other nephew, Richard Paradine, looked in, and I asked him to stay whilst I went and washed my hands. He did so. When I came back I took the attaché case and drove out here. At half past six I opened the case and discovered that the blue-prints were missing. You asked why I said that this was a family affair. I am telling you that no one outside the family had any possible opportunity of taking those prints.”