"Yes," I said. "I dare say they did. A lot of people have wanted them, but unfortunately they're not for sale."
Sonia laughed softly. "The exact price we paid for them," she said, "was twelve thousand pounds."
I sat up with a jerk. This time my surprise was utterly genuine.
"You bought them!" I said incredulously. "Bought them from some one in the Admiralty?"
Again Sonia shook her head. "Don't you remember what you read in the Daily Mail about the robbery at your offices in Victoria Street?"
I stared at her for a second, and then suddenly the real truth dawned on me.
"So George sold them to you?" I said.
She nodded. "Ever since you went to prison the business has been going to pieces. He wanted money badly—very badly indeed. Dr. McMurtrie found this out. He found out too that there was a copy of the plans in the office, and—well, you can guess the rest. The burglary, of course, was arranged between them. It was meant to cover your cousin in case the Government found out that the Germans had got hold of the plans."
"And have they found out?" I asked.
Again Sonia shrugged her shoulders. "I can't say. The doctor and my father never tell me anything that they can keep to themselves. Most of what I know I have picked up from listening to them and putting things together in my own head afterwards. I am useful to them, and to a certain point they trust me; but only so far. They know I hate them both."