It was the high-pitched cry of a woman in terror. It rang out sharply over the ominous silence, resting on that quiet island. And it was not far away. Clapping my hand to my pocket to make sure I had the automatic pistol which Carstairs had pressed upon me before he left, I dropped the knapsack and darted from the cave.  
I had no clear purpose in my mind, I think. Did not Edmund Burke tell us that the age of chivalry is dead? But half the battle in this curious work of ours is knowing what the other fellow is up to and I have never been able to sit down quietly under uncertainty.
 
Swiftly I mounted the rocky slope from the shore. Behind me the gulls uttered their mournful cries as they hung above the placid sea and in the woods around me there was the loud chatter of birds. But there was no sound of human voice.
 
Then suddenly I came upon Marjorie Garth in a little open space between two moss-grown boulders. Though I could hardly believe my own eyes there was no mistake about it; for her face was turned towards me. And she was struggling in the arms of Custrin. Her face was very pale and in her grey eyes was a look of despair which I shall not easily forget. She was wearing no hat and her gold-brown hair tossed to and fro as with one hand thrust in her opponent's face, she fought desperately to keep him off.
 
It all happened in a flash. The next thing I knew, I felt the bite of my knuckles in Custrin's damp neck as, my hand firmly clutching his collar, I tore him backwards. All my resentment against this false, sleek, smooth-spoken creature welled up within me and I exulted to feel him stagger and wilt, then crumple up in a grasp which I willed to be as violent and brutal as mind and muscle could make it.
 
Caught unawares he reeled backwards inert, for a fraction of a second a dead weight in my hold. But then he reacted. I felt his wiry frame stiffen as he struggled to elude me. But I held fast and swinging him round, gave him my fist in his face.
 
It was the force of my own blow that sent him from my hands,—staggering against a rock which brought him up standing. A single word he spoke.
 
"Herr!" he cried and the word burst in a kind of sob from his throat. In the crisis his native tongue came to his lips and in that moment I knew Dr. Custrin for a German.
 
There was murder in his quick, black eyes. His hand clawed for his hip-pocket but I was at him at once, driving for his face again. This time he dodged the blow and I felt my wrist rasp on the rough boulder behind him. For all his pretty drawing-room ways he was game enough, and with outstretched hands made at my throat.
 
But I drew back swiftly and as he came at me, let fly with my left to the point of the chin. He stopped dead, his eyes goggling, his head sagging on his shoulders. Then he crumpled up in a mass at my feet.
 
I turned to Marjorie. She stood, where I had found her, against the other boulder, dabbing at her lips with her handkerchief, her breath coming and going in quick gasps.
 
"The beast!" she said and her voice broke. "The beast!"
 
Then, plaintively like a little child, she cried:—
 
"Where is Daddy? Oh, please, will you take me to him...."
 
"Your father has gone to fetch the yacht," I answered and broke off in sheer perplexity. Where was the Naomi? The unexplained appearance of Marjorie on the island complicated matters horribly. Alone I was content to face the prospect of eluding Clubfoot and the vengeance he would surely try to wreak on me. But with a woman....!
 
There was nothing for it but to put into execution the plan I had already formed. I must find—and that without an instant's delay—a hiding-place and withdraw there with the girl. That must be my first care. The future must look after itself.
 
And the cipher? My intention had been to scale the terraced rock to follow up the next clue. There were caves there in which we could shelter and the topmost terrace would surely afford a view over the sea and enable us to sight the Naomi as soon as she appeared off the island.
 
We would make for the terraces and lie, snugly hidden there, until the yacht came back. And in this way I might also continue to follow up the clue to the treasure. But we must have food and arms. We should have to go back to the cave on the shore.
 
I looked at Custrin. He lay like a log.
 
"Come," I said to Marjorie, who was now looking at me curiously.
 
I glanced down at my clothes and realised that my appearance must be nothing less than forbidding—my face grimy and unshaven, my white drill torn and stained and my boots all soggy with sea-water.
 
"You look so tired.... and so grave," she said. "What can have happened?"
 
"Let us go back to the camp," I rejoined, "and I'll tell you as we go."
 
"What about.... him?" she asked and looked at the prone form of the doctor.
 
"He'll sleep it off!" said I, "and the longer his slumbers last the better I shall be pleased!"
 
"But we can't go away and leave him like this!" she expostulated.
 
"When you have heard my story," I rejoined, "you will think as I do. He'll be all right. He's stirring already. Come! Let's go back to the shore!"
 
As we turned in the direction of the beach, I said:—
 
"But how on earth did you come to be here? What has happened to the Naomi?"
 
A little red............