“So, Watson ...?” he asked.
“Yes, Holmes,” I said. “I am ready.”
“And I am very glad to have you once again at my side.”

This is rather brilliantly executed. The tone, the style, the very essence of what is so marvelous about the Holmes stories is captured here, and while Holmes Rides Again may put too much of a modern twist on a story which is truly and elegantly bound by a detailed historical atmosphere, that's the idea you get.

IT is, of course, not perfect. it's too long for a Holmes work, and some of the detail of the streets, the background of London if you will, is forced through probably because it's so far a representation of a London long, long gone. Still, for all that you realise it isn't Doyle, it's a Doyle attempt actually done very well indeed.

You can perhaps look at it less charitably and argue it's fanfiction. I've read many a fanfic in my time which, given the style and quality of the writing, I would have eagerly paid for. I guess that's where being a known author comes into play.