"A Serbian spy, Stefan Drontoff," replied the man. "Do

He advanced to descend the ladder but Matthews was before him. Producing an electric torch from his pocket, Matthews slipped down the stair with Gordon close behind. There was a pause, so tense that it seemed an eternity to Desmond, as he waited half-way down the ladder with the musty smell of the cellar in his nostrils. Then Matthews cried:

"Let me look!" Gordon broke in. Then Desmond heard him exclaim.

"It's Nur-el-Din's French maid! It's Marie... she's been stabbed in the back!"

Desmond suddenly felt rather sick. This progress from one deed of violence to another revolted him. The others crowded into the cellar; but he did not follow them. He remained at the top of the trap, leaning against the wall, trying to collect his thoughts.

Barbara Mackwayte was now his sole preoccupation. If anything had happened to her,--it was through his fault alone; for he began to feel sure she must have come to the Mill House in his absence. What then had become of her? The blood-stained toque pointed to foul play. But if they had murdered her, what had they done with the body?

His thoughts flew back to his interview with Nur-el-Din upstairs on the previous afternoon. He remembered the entrance of the maid and the dancer's hurried exit. Might not Marie have come to tell her that Barbara Mackwayte was below asking for her? It was very shortly after this interruption that, crouching on the roof of the shed, he had heard that muffled cry from the house and seen Rass enter the bar and speak with Strangwise. He had seen, too, the maid, Marie, in earnest conversation with Strangwise by the back gate on the fen. Had both Marie and Rass been in league with Strangwise against the dancer? And had Nur-el-Din discovered their treachery? His mind refused to follow these deductions to their logical sequence; for, black as things looked against Nur-el-Din, he could not bring himself to believe her a murderess.

But now there were footsteps on the ladder. They were all coming out of the cellar again. As soon as Francis saw Desmond's face, he caught his brother by the arm and said:

"The open air for you, my boy! You look as if you'd seen a ghost! I should have remembered all you've gone through!"