"I should have added, and not know it," the Sumatran said. "If you fail and are caught, I shall know it almost at the same instant. Then I shall have to find another way."

"But the information!" Freddy Farmer cried in true German bewilderment. "What if it falls into the hands of the British?"

"The very least of my worries, for it is no worry at all," Serrangi replied promptly. "It would do them no good. It would give them headaches, and it would probably drive them mad in the end. But they would never be able to decipher what it meant. That, my two friends, is why Serrangi holds the position he does. No man alive can read my code without the key. And only one other man knows the key at a time!"

Dave frowned, started to ask what that meant, and then the truth of the statement hit him right between the eyes. To be given Serrangi's code key was to be handed your death warrant. When you had served his evil purpose, no matter what it might be, you died ... and the next man in Serrangi's death and blood dealings was given the key.

"The one who knows the key now is at Raja?" Dave grunted.

"That is so," the Sumatran said. "And one of the Japanese Emperor's most trusted generals. To him I gave it personally. And I know the thoughts that fill your mind, now. When I have closed my work, my business, with him? Perhaps, and perhaps not. When the Japanese take Singapore there must be some one to govern and rule. Perhaps I will tire of operating the Devil's Den. Who knows ... but myself? But enough of this talk. Our work is not yet done."

Serrangi gave a wave of his hand to dismiss the loose talk, and for a moment frowned at the thread of grey smoke that spiralled upward from his cigarette. Then suddenly he nodded as though he had made up his mind on something.

"There are many Royal Air Force fields here in Singapore," he grunted. "Perhaps, though, it would be best to steal your plane from the Municipal Airport which the Government has taken over. I happen to know that it is not so well guarded as the others."

"What about the planes there?" Dave asked in a voice he had to fight to keep steady. "We would want nothing bigger than a two seater. To steal a bomber would be impossible. Too much to do before taking it off."

"There is no need to worry!" Serrangi said a bit sharply. "There are planes of all types at the Municipal Airport. And the fools ... they keep them all lined up in rows, as though they had them on display for sale. I do not feel that you will have much difficulty. True, there are armed guards about the field. But you two have heard the sound of rifles and machine guns shooting at you before now, eh?"