Kennedy shrugged his shoulders—­he even had the shrug.

“Figure to yourself, monsieur,” he said.  “Ze great Kennedy, ze detectif Americain—­to put it tersely in our own vernacular, wouldn’t it be a fool thing for me to appear at the Vesper Club where I should surely be recognized by someone if I went in my ordinary clothes and features? Un faux pas, at the start? Jamais!”

There was nothing to do but agree, and I was glad that I had been discreetly reticent about my companion in talking with the friend who was to gain us entrance to the Avernus beyond the steel door.

We met my friend at the Riviera and dined sumptuously.  Fortunately he seemed decidedly impressed with my friend Monsieur Kay—­I could do no better on the spur of the moment than take Kennedy’s initial, which seemed to serve.  We progressed amicably from oysters and soup down to coffee, cigars, and liqueurs, and I succeeded in swallowing Kennedy’s tales of Monte Carlo and Ostend and Ascot without even a smile.  He must have heard them somewhere, and treasured them up for just such an occasion, but he told them in a manner that was verisimilitude itself, using perfect English with just the trace of an accent at the right places.

At last it was time to saunter around to the Vesper Club without seeming to be too indecently early.  The theatres were not yet out, but my friend said play was just beginning at the club and would soon be in full swing.

I had a keen sense of wickedness as we mounted the steps in the yellow flare of the flaming arc-light on the Broadway corner not far below us.  A heavy, grated door swung open at the practised signal of my friend, and an obsequious negro servant stood bowing and pronouncing his name in the sombre mahogany portal beyond, with its green marble pillars and handsome decorations.  A short parley followed, after which we entered, my friend having apparently satisfied someone that we were all right.

We did not stop to examine the first floor, which doubtless was innocent enough, but turned quickly up a flight of steps.  At the foot of the broad staircase Kennedy paused to examine some rich carvings, and I felt him nudge me.  I turned.  It was an enclosed staircase, with walls that looked to be of re-enforced concrete.  Swung back on hinges concealed like those of a modern burglar-proof safe was the famous steel door.

We did not wish to appear to be too interested, yet a certain amount of curiosity was only proper.

My friend paused on the steps, turned, and came back.

“You’re perfectly safe,” he smiled, tapping the door with his cane with a sort of affectionate respect.  “It would take the police ages to get past that barrier, which would be swung shut and bolted the moment the lookout gave the alarm.  But there has never been any trouble.  The police know that it is so far, no farther.  Besides,” he added with a wink to me, “you know, Senator Danfield wouldn’t like this pretty little door even scratched.  Come up, I think I hear DeLong’s voice up-stairs.  You’ve heard of him, monsieur?  It’s said his luck has changed.  I’m anxious to find out.”