I tried hard to find an empty carriage; but the train was full and there was no such luxury to be had. Besides, guards, porters, and station- masters were all shouting to me to get inside somewhere, and a score of heads attracted by the commotion appeared at the windows and added to my discomfort. Finally I took refuge in a carriage which seemed less crowded than the rest--having but two occupants. Alas! to my horror and dismay I discovered when the train had started that I had intruded myself on a palpably honeymoon couple, who glared at me in such an unfriendly manner that for the next hour and a half, without respite, I was constrained to stand with my head out of the window. Even in the tunnels I had no encouragement to turn my head round. This was bad enough, but it would have been worse had it not happened that, in craning my head and neck out of the window, I caught sight, in the corner of the carriage--next to mine, of half of the back of a head which I felt sure I knew. It belonged, in fact, to Michael McCrane, and a partial turn of his face left no doubt on the matter. I had run my man down already! I smiled to myself as I contemplated the unconscious nape of that neck and recalled the gibes of the commercial traveller and the uncomfortable stare of the man in the corner. What should I do? The train would stop for two minutes at Bletchley, and not again until we reached Rugby. Should I lay my hand on his shoulder at the first place or the second? I wished I could have dared to retire into my carriage and consult my timetable about trains back. But the consciousness of the honeymoon glare at my back glued me to the window. I must inquire at Bletchley and act accordingly. We were beginning to put on the break, and show other signs of coming to a halt, when I was startled by seeing McCrane stand up and put his head out of the window. I withdrew as hastily as I could; not daring, of course, to retreat fully into the carriage, but turning my face in an opposite direction, so as to conceal my identity. I could not guess whether he had seen me or not, it had all occurred so quickly. If he had, I might have need of all my strategy to run him to earth. As the train pulled up I saw him lower his window, and, with anxious face, make a sudden bolt across the platform. That was enough for me. I darted out too, much to the satisfaction of my fellow-travellers. "When's the next train back to Euston?" "Take your seats!" bawled the guard, ignoring me. "When does the next train go to Euston?" "There's a time-table there."