La Touche hesitated a moment. What if it was a plant after all? Finding Boirac here alone was certainly suspicious. But the cut at least was genuine. La Touche could see the red stain slowly spreading across the handkerchief.

‘Well, messieurs, I’m sorry I can’t hold the door open. Kindly either come in and wait, or, if you prefer it, call back later on.’

La Touche made up his mind. They were armed and on their guard. As he entered the hall his left hand in his overcoat pocket crept to the handle of his magazine pistol, and he quietly covered the manufacturer.

The latter closed the front door behind them and led the way to François’s room. It was in darkness, but Boirac, entering before the others, turned on the light.

‘Come in and be seated, gentlemen, if you please,’ he said. ‘I should like a word with you before François returns.’

La Touche did not at all like the turn affairs were taking. Boirac’s conduct seemed to him to grow more and more suspicious. Then he reflected again that they were two to one, were armed, and keenly on their guard, and that there could be no cause for uneasiness. Besides, there could be no trap. Boirac had preceded them into the room.

The manufacturer pulled together three chairs.

‘If you would kindly be seated, gentlemen, I would tell you what I want you to know.’

The detectives obeyed, La Touche still keeping his pistol turned on his host.

‘Gentlemen,’ went on the latter, ‘I owe you both a very full apology for having played a trick on you, but I am sure, when I have explained the extraordinary circumstances in which I am placed, you will hold me, if not justified, at least excused. And first, I must tell you that I know who you are, and on what business you came to Paris.’