At midnight I awoke suddenly. My mind was alert and bright, with that extreme clarity which comes sometimes after working hard on a problem. The moon was pouring a pale light over the window sill. It bathed my face in its lambent glow as I lay there for a moment, wondering what chemical time bomb had exploded in my brain. I looked at my watch. It was midnight. I got up and looked out. Spreading up from the delta, curling over the fishing fleet and the canneries, flowing between the houses and filling the streets as the incoming tide runs in the channels and covers the stones of a rocky shore, the fog filled the hollows and smoothed over the humps of the city, until at last all but the higher tops of the buildings sank under the woolly wave. The sense of urgent discovery had faded from my mind. There was something I had to remember, I knew, something that my mind had worked out as I slept, but, though I searched for a clue, it would not come. Idly, in my wakefulness, I watched the fishing fleet as it slowly sank in the mist, until at last even the tall masts were gone. A bad night to be out fishing, I thought, but a good night for smugglers or anybody who didn't want to be seen. "By God ... that's it! That must be it!" The key had turned. The clue had been found. The sudden excitement of discovery set the pulse pounding in my ears until I thought it must be audible, like the ticking of an alarm clock. I opened the closet and rummaged in my suitcase for the sweater and light windbreaker and my old, cut-down paratrooper boots that I had brought from my apartment. It would be cold where I wanted to go, and go I must, virus or no virus. I had just finished blousing my pants over my socks, GI style, and was moving towards the door when it opened, and Pat, holding a book in one hand, yawned in my face. "What's all the noise about?" she said, standing there sleepily in her rumpled pajamas. The yawn froze in amazement and then snapped shut as her eyes travelled over me. "Well, I declare!" she said. "Where on earth are you going?" "I haven't time to explain," I said in a low voice, afraid of waking Hallam. She suspected as much. "Have you told the Chief?" "No, I don't want to tell him just now. I've got a hunch on this virus warfare idea of his. It's only a wild guess and I've got to go out to follow it up. He might not want me to take the risk of catching flu." "I don't want you to either." "I'm sorry, Honey, but I've got to do it. There's too much riding on this thing to let our personal affairs interfere." "But you said yourself it's only a wild guess. Why risk our whole future on that?" "Look, I'm going to keep away from people as much as possible, but I'm going out just the same. This may be the last chance I'll ever get to see if the boss is right." "Then I'm going with you." "Oh, hell! This is no job for a woman." "It's no job for one man! Either I go or I wake up Dr. Hallam."