e o'clock next morning I
left the car in Wardour Street and walked with the stranger to the
frowsy house in Providence Court, where to my great surprise Gerald
Tracy opened the door. He laughed at my astonishment, but with a
gesture indicative of silence, he merely said:

"Hallo, Hargreave! Back all right, eh?"

Then he admitted the Dutchman and closed the door.

Tracy was evidently there to hold consultation with the stranger whose
entrance into England was unknown. He would certainly never risk a
long stay in that house, for the stout, bald-headed man had, I knew,
no wish to come face to face with Benton or any other officer of the
C.I.D.

Certainly something sinister and important was intended.

On calling at Half Moon Street, after having breakfasted, I found
Duperre there.

"Rayne wants you to go down to the Pavilion Hotel at Folkestone and
garage the car there," he said. "He and I are running a risk in a
couple of night's time--the risk whether Benton identifies us. We both
have tickets for the annual dinner of the staff of the Criminal
Investigation Department, which is to be held in the Elgin Rooms."

"And are you actually going?" I asked, much surprised.

"Yes. And our places are close to Benton's! He'll never dream that the
men he is hunting for everywhere are sitting exactly opposite him as
guests of one of his superiors."

Boldness was one of Rudolph Rayne's characteristics. He was fearless
in all his clever and ingenious conspiracies, though his cunning was
unequaled.

As I drove down to Folkestone I ruminated, as I so often did. No doubt
some devilish plot was underlying the acceptance of the high police
official's invitation to the staff dinner.

Its nature became revealed a few days later when, on opening my
newspaper one morning, being still at Folkestone waiting in patience,
I read a paragraph which aroused within me considerable interest.

It was to the effect that Superintendent Arthur Benton, the well-known
Scotland Yard officer, had, after the annual dinner a few nights
before, been suddenly taken ill on his way home to Hampstead, and was
at the moment lying in a very critical condition suffering from some
mysterious form of ptomaine poisoning, his life being despaired of.

I was quite unaware until long afterwards of the deeply laid attempt
upon Benton's life, how the mysterious Dutchman was really a waiter
much wanted by the French police for a poisoning affair in Marseilles,
and