“Not bad, not at all bad,” muttered the other, and the twinkle in his eyes faded.

“We know the important things, too, all that concerns you, from your forced resignation two years ago down to your talk yesterday with the girl at Notre-Dame.  So how can you fight us?  How can you shadow people who shadow you?  Who watch your actions from day to day, from hour to hour?  Who know exactly the moment when you are weak and unprepared, as I know now that you are unarmed because you left that pistol with Papa Tignol.”

For a moment Coquenil was silent, and then:  “Here’s your money,” he said, returning the envelope.

“Then you refuse?”

“I refuse.”

“Stubborn fellow!  And unbelieving!  You doubt our power against you.  Come, I will give you a glimpse of it, just the briefest glimpse.  Suppose you try to arrest me.  You have been thinking of it, now act.  I’m a suspicious character, I ought to be investigated.  Well, do your duty.  I might point out that such an arrest would accomplish absolutely nothing, for you haven’t the slightest evidence against me and can get none, but I waive that point because I want to show you that, even in so simple an effort against us as this, you would inevitably fail.”

The man’s impudence was passing all bounds.  “You mean that I cannot arrest you?” menaced Coquenil.

“Precisely.  I mean that with all your cleverness and with a distinct advantage in position, here on the Champs Elysees with policemen all about us, you cannot arrest me.”

“We’ll see about that,” answered M. Paul, a grim purpose showing in his deep-set eyes.

“I say this in no spirit of bravado,” continued the other with irritating insolence, “but so that you may remember my words and this warning when I am gone.”  Then, with a final fling of defiance:  “This is the first time you have seen me, M. Coquenil, and you will probably never see me again, but you will hear from me. Now blow your whistle!”

Coquenil was puzzled.  If this was a bluff, it was the maddest, most incomprehensible bluff that a criminal ever made.  But if it was not a bluff?  Could there be a hidden purpose here?  Was the man deliberately making some subtle move in the game he was playing?  The detective paused to think.  They had come down the Champs Elysees, past the Ansonia, and were nearing the Rond Point, the best guarded part of Paris, where the shrill summons of his police call would be answered almost instantly.  And yet he hesitated.

“There is no hurry, I suppose,” said the detective.  “I’d like to ask a question or two.”

“As many as you please.”