As I had now decided to devote myself to finding the man known as the Dumpling, and to the clearing up of the mystery of my friend's death and of the opium den, the first question to be asked (it was the question I put to myself as I walked away from the inn) was, "Did the Dumpling really believe me to be Grant?" If that were so, it was possible that Grant had to the last successfully maintained his disguise, and had met his death accidentally while shadowing the fugitives, who had probably made their escape by way of the water. Or it was possible that, without suspecting the supposed Chinaman to be Grant, something may have happened after my departure to arouse the Dumpling's suspicions in regard to Grant's good faith, in which case short work would no doubt be made of the intruder. What was more likely, for instance, than that, hearing the uproar downstairs, after I had locked myself in the kitchen, and fearing that I was being murdered, Grant had rushed down to my assistance, and so betrayed himself? In which case, the Dumpling would have made no bones about knocking him on the head, or otherwise despatching him and throwing the body into the river. But, apart from the question whether my friend had met his death by accident or by intention, the facts seemed to justify me in assuming that the Dumpling had really believed me to be Grant, the detective. The reader will remember that, after I had locked myself in the kitchen, the Dumpling had called out, "Don't say you haven't killed your man! He mustn't leave the place alive. It's Robert Grant, the detective. I had word that he'd tracked us, and meant trying to get in here to-night." All this seemed strongly to point to the fact that the Dumpling _did_ indeed believe me to be the hated detective. How he had got wind of Grant's intention to effect an entrance to the den, or how Grant had contrived successfully to effect that entrance, and to disarm suspicion, I did not know; but, supposing that news of the threatened danger had only reached the ears of the Dumpling a few moments before my arrival, and before he had time to turn his suspicions in other directions--the fact that the news was followed by the entrance of a suspicious stranger, who could give no better explanation for his presence than a lame and apparently trumped-up story about a commission to write a magazine article on opium dens, would certainly lend colour to the assumption that I was the expected man. The determined and desperate efforts which had subsequently been made to murder me, all seemed to point the same way; and I decided to start my investigation by assuming that the Dumpling and his accomplices had believed, and still believed, me to be none other than Robert Grant, the detective.