But Gregory remembered with dismay that Grauber and his colleagues had a habit of perfecting all their arrangements down to the last detail beforehand, so the real probability was that now that the balloon was actually due to go up he had nothing whatever to do but sit back and watch the well-oiled wheels of the Nazi machine begin to turn as it roared forward on the lines that had been so carefully laid down for it.
For a second he thought of trying to argue Grauber out of his decision. He knew well enough that no plea for mercy would have any effect, but if he said that he spoke German, had understood Grauber's remarks that the Blitzkrieg was being launched at that moment and that he was a German Fifth Columnist who had work to do for Germany, there was just a possibility that Grauber might have let him go; particularly as Fifth Columnists in countries outside Germany were largely recruited from the criminal classes, which would lend a certain plausibility to such a story. But the trouble was that if he once opened his mouth Grauber still might recognise him and, as they were alone, kill him without further argument; so he decided that he dare not risk it.
Having spoken on the bedside telephone to the man on duty downstairs, while never taking his solitary eye off Gregory for a single second, Grauber replaced the receiver. With his free hand he took out his handkerchief and dabbed at a small boil on his chin, and Gregory caught a whiff of the rather sickly perfume that he always affected. Then the German perched himself on the end of the bed once more as they waited for the night-porter and the police to arrive.
Gregory, meanwhile, was wondering frantically how he could get out of this wretched mess in which he had landed himself; but the evidence against him as he stood there was so obvious that any plea of innocence would only be laughable. The Dutch police were efficient and it was most unlikely that they would allow a burglar who had been caught with a weapon in his hand the least loophole for escape on the way to the police-station; in fact, he would almost certainly be handcuffed to one of them. In the course of the next few days he would come up for trial, as even an invasion was unlikely to interfere with the normal criminal procedure in a coast city like Rotterdam that was many miles from the German frontier. Then he would be sent down for two or three years' hard labour, and he did not see how even Sir Pellinore would be able to help him.
He had got thus far in his gloomy speculations when there was the sound of a pass-key turning the lock of the outer door and a moment later the night-porter entered the room with a plain-clothes man, who had 'hotel detective' written all over him, and two uniformed policemen.
Grauber immediately addressed the plain-clothes man in French. 'As you probably know, my friend, Madame de Swarle, has just left the hotel. I had to see her on urgent business but I could not get here before two o'clock. I have had no opportunity to secure accommodation for myself, so she said before leaving that I had better take over her suite and sleep in this room for what is left of the night. She had hardly been gone five minutes when I went into the bathroom and caught this fellow in the act of wriggling through the window. Fortunately, I had a gun on me so I was able to hold him up, but you will notice that he is armed; and if I had not drawn my own weapon very quickly he would have shot me. Kindly remove him. I will visit the police-station in the morning to charge him with felonious entry.'
The detective looked at Gregory. 'Have you anything to say?'
Gregory silently shook his head, but from under the brim of his hat he snatched a glance at the clock; its long hand now had only half a minute to go before it reached the hour.
'Right, then,' the detective nodded to the policemen. 'You'd better take him along, boys.'
Grauber had lowered his gun at the entry of the police. Gregory suddenly stepped back and raised his, pointing it not at the police but at Grauber. 'One moment!' he cried, using the husky voice in which he had spoken to the Baroness. 'Remain quite still all of you, or I will kill this man,'
The night-porter had started forward, but he checked himself. For half a moment all six men remained rigid, like a set tableau. Gregory was listening with all his ears for the hum of aeroplane engines, praying that the Germans would be on time. The others were staring at him, wondering what he meant to do. A full minute passed, but no sound broke the stillness.
'Well?' exclaimed Grauber at last, turning with a sneer towards the two policemen. 'Are you going to remain standing there all night while this man threatens me?'
In vain Gregory strained his ears. For once the Germans were late in launching their programme.
Knowing that he could hold the situation no longer he played another card. Lifting his free hand, he jerked down the handkerchief that covered the lower part of his face.
'Gott in Himmel! Sallust!' With a shout Grauber sprang up from the bed. But Gregory had him covered, so he could only stand there snarling with anger at the thought of the opportunity to revenge himself that he had now lost.
'So you recognise me at last,' Gregory said smoothly. 'I am glad of that, because I wanted these gentlemen to be given clear proof that I'm somebody who is known to you.' He swung round to the others. 'Now let me make it clear what has been happening here. I am not a burglar; I've stolen nothing; and the only thing with which this man can charge me is with breaking into Madame de Swarle's suite. If he does that I shall counter-charge him, because I challenge him to prove that he has any right here either.
Again, if he charges me with threatening his life I shall charge him with threatening mine; and on that count I have the advantage because when you entered this room he was actually holding me up with his pistol.'
The four Dutchmen looked extremely puzzled. The whole matter had now taken such a totally different turn from anything they had anticipated, and while they followed Gregory's reasoning they did not see what they ought to do. At last the detective said:
'That's all very well; but it was the other gentleman who called us in and he wouldn't have done that unless you had been threatening him.'
'Oh yes, he would,' said Gregory: 'because he had the draw on me and it's in his interests to get me locked up for the night —or longer if he can manage it—so that I'm out of his way; but I'll bet you a hundred gulden to twenty-five cents that if you take me to the police-station he'll never turn up to charge me with anything in the morning.'
'Can you explain what you were doing here?' asked the detective.
'Yes. You Dutchmen have got yourselves mixed up in an international quarrel; I am an Englishman, at present employed upon a special mission for my country; while that fat, repulsive thug at the end of the bed there . . .' Suddenly he broke off, and exclaimed: 'Listen!'
It was now three minutes past three; no aeroplanes were droning overhead but in the silence that followed his exclamation they could all hear the sound that he had been the first to catch: it was a low, irregular thudding in the distance.
'D'you know what that is?' he said quickly.