The concept of this collection is that it contains a mix of genres: some straight-up mystery stories where every bizarre occurrence can be explained away, and some speculative fiction stories where the solution to the mystery involves something like aliens, Cthulhu, or travel to a parallel universe. In almost all of the stories I was able to tell whether the supernatural occurrences were "real" almost immediately, well before the reveal, but the variety of genres was fun nevertheless. As in any collection of short stories, some are better than others, but there were a number of stories I absolutely adored and only one or two I truly disliked. Some of my favorites included (with some fairly minor spoilers):
-Naomi Novik does her fanfic origins proud in "Commonplaces." She directly addresses the question of exactly how deep the connection between Holmes and Watson runs. I squeed SO DAMN HARD, even though it's a bittersweet story. Also, I really like Novik's version of Irene Adler.
-Stephen King's descriptively titled "The Doctor's Case," wherein Watson solves the mystery before Holmes. It turns out that my fondness for super-competent!John in the BBC-verse translates to other versions of our detective duo as well.
-"The Singular Habits of Wasps" by Geoffrey Landis, a brilliantly unsettling take on Jack the Ripper.
-Neil Gaiman's "A Study in Emerald." If you don't already know why this story is a dark gem, you can also read it on Neil's website.
-"The Adventure of the Pirates of Devil's Cape" by Rob Rogers. Inspired lunacy with an albino alligator and PIRATES! Also, BAMF!Watson fights a giant.
-For an example of a pro writer dipping into that beloved fandom genre of crack, I loved "The Adventure of the Lost World" by Dominic Green. Those in Sherlock fandom may be especially amused to note that this story contains a dinosaur. (Yes, watchalong folks, it is better than the movie with Gareth David Lloyd.) As if the prospect of Sherlock + dinosaur isn't tantalizing enough, I really must share this selection of dialog between Holmes and Watson.
[Sherlock said,] "In the past seven days, on Hampstead Heath, there have been seven attacks up on street musicians, each the player of a trombone of some description, and each attacked, if those who heard the attacks are to be believed, whilst executing the closing bars of Gustav Holst's Thaxted. In each case, the victim appears to have been attacked from above, the flesh crushed and cut, the bones splintered, the capital extremity entirely missing in many cases. Each victim's body was also notable for the stench of corruption which hung about it, like gas gangrene."
"Accidental death has been ruled out, then? A recurrent trombone malfunction of some order–"
"–has already been checked for."
Trombone malfunction! If this story was online, I'd be flailing around with capslock and exclamations about winning the internet. :-P Also, I have decided that my personal canon is that Anderson plays the trombone.
In summary, if you're looking for a fun bunch of stories putting familiar characters in unfamiliar situations or you want some [mostly] gen Sherlock Holmes fanfic you can carry around in book form, I recommend The Improbable Adventures of Sherlock Holmes.