Not bad, but no the best, neither. Sherlock has amazing cases, in which his deduction skills shine bright. This time, his investigation takes us from an opium den in London to Kent, and it is an entertaining ride. But I found this case extremely similar to the one from another story, the one titled "A Case of Identity", which also tells about a missing man, and a matter of disguise (I could tell who the culprit was before Sherlock gave his solution). Still, not bad, but it could have been better; as I like to say, with Sherlock Holmes, it is never time wasted!