“Then what were you doing on the train with the slipper?” asked Hilton sharply.

“I was going to Liverpool, sir!” snapped The Stetson Man, turning on him.  “I was going to try to get aboard the Mauretania and then make terms for my life!  What happened?  I slipped out at Birmingham for a drink—­grip in hand!  I put it down beside me, and Mr. Cavanagh here, all in a hustle, must have rushed in behind me, snatched a whisky and snatched my grip and started for H—!”

A vivid flash of lightning flickered about the room.  Then came the deafening boom of the thunder, right over the house it seemed.

“I knew from the weight of the grip it wasn’t mine,” said Dexter, “and I was the most surprised guy in Great Britain and Ireland when I found whose it was!  I opened it, of course!  And right on top was a waistcoat and right in the first pocket was a telegram.  Here it is!”

He passed it to me.  It was that which I had received from Hilton.  I had packed the suit which I had been wearing that morning and must previously have thrust the telegram into the waistcoat pocket.

“Providence!” Dexter assured me.  “Because I got on the station in time to see Hassan of Aleppo join the train for H—!  I was too late, though.  But I chartered a taxi out on Corporation Street and invited the man to race the local!  He couldn’t do it, but we got here in time for the fireworks!  Mr. Cavanagh, there are anything from six to ten Hashishin watching this house!”

“I know it!”

“They’re bareheaded; and in the dark their shaven skulls look like nothing human.  They’re armed with those damned tubes, too.  I’d give a thousand dollars—­if I had it!—­to know their mechanism.  Well, gentlemen, deeds speak.  What am I here for, when I might be on the way to Liverpool, and safety?”

“You’re here to try to make up for the past a bit!” said a soft, musical voice.  “Mr. Cavanagh’s life is in danger.”

Carneta entered the room.

The light played in that wonderful hair of hers; and pale though she was, I thought I had never seen a more beautiful woman.

“Tell them,” she said quietly, “what must be done.”

Soar glanced at me out of the corner of his eyes and shifted uneasily.  Hilton stared as if fascinated.

“Now,” rapped Dexter, in his strident voice, “putting aside all questions of justice and right (we’re not policemen), what do we want—­you and I, Mr. Cavanagh?”

“I can’t think clearly about anything,” I said dully.  “Explain yourself.”

“Very well.  Inspector Bristol, C.I.D., would want me and Hassan arrested.  I don’t want that!  What I want is peace; I want to be able to sleep in comfort; I want to know I’m not likely to be murdered on the next corner!  Same with you?”

“Yes—­yes.”

“How can we manage it?  One way would be to kill Hassan of Aleppo; but he wants a lot of killing—­I’ve tried!  Moreover, directly we’d done it, another Sheikh-al-jebal would be nominated and he’d carry on the bloody work.  We’d be worse off than ever.  Right! we’ve got to connive at letting the blood-stained fanatic escape, and we’ve got to give up the slipper!”