"She was trying to listen to what I was saying to the English girl—Mademoiselle Flossie, she called herself, and when she went away with her friends she threw me a note with two words on it—'prenez garde!' I know it struck me as being rather queer, because——"
He hesitated. The Duke nodded.
"Go on!" he said.
"Well, I may as well tell you everything," Guy continued, "even if it does sound rather like rot. All the time I was in Vienna and on the journey to Paris I fancied that I was being followed. I kept on seeing the same people, and a man who got in at Strasburg—I had seen him before at the hotel in Vienna—tried all he could to pal up to me. I hate Germans though, and I didn't like the look of the fellow, so I wouldn't have anything to say to him, though I feel sure he tipped the conductor to put him in my compartment. I gave him the slip at the railway station at Paris, but I'm almost sure I saw him that night at the Café Montmartre."
"Your story," Monsieur Grisson said quietly, "becomes more and more interesting. Monsieur le Duc here has hinted at some slight indiscretion of yours on the night of your arrival in Paris. I have some influence with the Government here, and I think I can promise you some very substantial help in return for the information you have given us. But I want you to turn your thoughts back to the night you spent by the railroad. Can you remember anything further about it, however trifling, which you have not told us?"
Guy leaned back in his chair and thought for a moment.
"By Jove," he declared, "there is something which I forgot altogether. Just before that little party in the railway saloon broke up the chap in the car who had been writing left his seat, and a loose page of paper fluttered through the window."
The two men leaned across the table almost simultaneously.
"What became of it?" the Duke asked sharply.
"I picked it up and put it in my pocket," Guy answered.