This is quickly supplied. Waterhouse knows, and has proved to Earl Comstock, that strange information is in the air, dotting and dashing furtively from a small number of feeble transmitters scattered around Luzon and the surrounding waters, encrypted using the Arethusa system. Lawrence and Alan have known for two years now that Rudy invented it, and from the decrypts chattering out of digital computers in Bletchley Park and Manila, they now know other things. They know that Rudy flew the coop late in 1943 and probably went to Sweden. They know that one Günter Bischoff, captain of the U-boat that plucked Shaftoe and Root out of the water, also ended up in Sweden, and that Dönitz persuaded him to take over the gold-running work that had been performed by U-553 until it ran aground off Qwghlm. The Naval Intelligence boys are fascinated by Bischoff, and so he had already been the subject of much research. Waterhouse has seen photos of him from his student days. The shorter of the two men he is peering at now could easily be the same fellow, now middle-aged. And the taller one, the one with the eyepatch, could most definitely be Rudy von Hacklheber himself.