In order to conduct his investigations with a minimum of suspicion, Marks had elected to enter San Diego in the guise of a derelict—a character which he had played to such perfection that two weeks after he arrived he found himself in court on the charge of vagrancy. Only the fact that the presiding magistrate did not believe in sentencing first offenders saved him from ten days in the workhouse, an opportunity which he was rather sorry to miss because he figured that he might pick up some valuable leads from the opium addicts among his fellow prisoners.
The only new point which he had developed during his stay in the underworld was that some one named Sprague, presumably an American, was the brains of the opium ring and had perfected the entire plan. But who Sprague was or where he might be found were matters which were kept in very watchful secrecy.
"I give it up," muttered the operative, shrugging his arms into a threadbare coat and shambling out of the disreputable rooming house which passed for home. "Work doesn't seem to get me anywhere. Guess I'll have to trust to luck," and he wandered out for his nightly stroll through the Chinese quarter, hoping against hope that something would happen.
It did—in bunches!
Possibly it was luck, possibly it was fate—which, after all, is only another name for luck—that brought him into an especially unsavory portion of the city shortly after midnight.
He had wandered along for three hours or more, with no objective in view save occasional visits to dives where he was known, when he heard something which caused him to whirl and automatically reach for his hip pocket. It was the cry of a woman, shrill and clear—the cry of a woman in mortal danger!
It had only sounded once, but there was a peculiar muffled quality at the end of the note, suggestive of a hand or a gag having been placed over the woman's mouth. Then—silence, so still as to be almost oppressive.
Puzzled, Marks stood stock still and waited. So far as he could remember that was the first time that he had heard anything of the kind in Chinatown. He knew that there were women there, but they were kept well in the background and, apparently, were content with their lot. The woman who had screamed, however, was in danger of her life. Behind one of those flimsy walls some drama was being enacted in defiance of the law—something was being done which meant danger of the most deadly kind to him who dared to interfere.
For a full minute Marks weighed the importance of his official mission against his sense of humanity. Should he take a chance on losing his prey merely to try to save a woman's life? Should he attempt to find the house from which the scream had come and force the door? Should he....
But the question was solved for him in a manner even more startling than the cry in the night.