And now with the darkness of night closed down over Duisburg, he was standing in what was left of the doorway of a bombed out house directly across Kholerstrasse from Number One Fifty-Six. Several times during the afternoon and evening he had passed by Number Sixteen in the faint hope that he might be able to see or hear something that would help him in deciding his next move. Once again, though, his hopes were in vain. From the outside Number Sixteen looked as though it hadn't been occupied since the start of the war. All of the window shades were drawn down, and half of the window shutters had been closed and bolted. The front door, which contained no window, was closed and locked. And not once had Dawson seen a single person go up or down the short flight of stone steps. If Number Sixteen was Intelligence headquarters in Duisburg, one certainly would not guess it from the looks of the outside of the building. Eventually convinced that he would gain nothing by parading past Number Sixteen, and having finally given up hope of spotting Freddy Farmer in any of the Kholerstrasse section eating places, Dawson had fallen back on his final and last hope. If this hope proved to be false and no good, then he was at the end of his rope. His mission to Germany would end in failure right there on the streets of Duisburg. And so he was playing his final card. From a good vantage point he was carefully studying the building that was Number One Fifty-Six Kohlerstrasse. The address of Major Crandall's agent, who was believed to reside there under the name of Heinrich Weiden. But did he? That question taunted Dawson as he surveyed the place, and half a hundred times he was tempted to go boldly over there, bang on the door of Number One Fifty-Six and demand of whoever answered that he be shown to Herr Heinrich Weiden's rooms at once. A tiny voice of caution warned against that move. For one thing, after two solid hours of watching the place, he had not seen anybody go in or come out. There wasn't so much as a single crack, of light showing, but of course that was probably due to the strict enforcement of the blackout regulations. In other words, Number One Fifty-Six was pretty much like Number Sixteen. No sign whatsoever that anybody occupied the place. Just the same, Dawson made no move to go over and find out for himself. He told himself that such a thing was silly. That he could probably wait all night, and not see a single thing of interest. And yet there was something that made him determined not to leave his place of concealment. Silly? Perhaps. But how was he to know if real Gestapo agents weren't watching the place? Ten days ago Heinrich Weiden had sent word through to Major Crandall that his old address was not good, and that he should be contacted at a new one. Ten days ago, but what had happened since?