OM - The Secret of Ahbor Valley

Excerpt: "Ommony managed to master his emotions somehow, but it was not easy, for here was proof of a system of spying that out-spied the Secret Service. How had the Lama learned that the stone had been entrusted to McGregor, to be given in turn to Macauley, to be taken to Tilgaun? Given that much information in the first place it might have been comparatively easy to trace the stone afterward, but—McGregor had surely not talked. Macauley and McGregor's sais were the only possibilities."