You won't read another book like this one for a while, I'll bet. The Somnambulist is an odd duck. It begins by telling the reader that the narrator has no literary skill and that he will occasionally tell outright lies. So you know from the start that he's about as unreliable as possible. And you don't even find out who he is until about three-quarters of the book is done. The plot involves a magician named Edward Moon, who's fallen on hard times. He does a great show, but he's no longer in fashion. The audiences are appreciative but small.
Moon's also supposedly a great detective in the Sherlock Holmes vein, though he does precious little detecting in this book that I can see. He's bored with life until he gets involved with what appears to be an interesting murder that leads to something far more sinister.
In both his magic act and his detecting, Moon is assisted by a man known only as The Somnambulist for reasons that escaped me entirely. In fact, there's a ton of back story referred to but which we're never given. Moon's relationship with his sister, who or what The Somnabulist might be, what happened to bring Barrabas to his sorry cell in Newgate, whether Innocenti is a genuine medium, and so on, are all left up in the air.
But never mind. For 300 pages, I was on board and having a fine time. The style is straightforward, there's humor, the characters and situations are oddly strange and strangely odd, even bizarre. Literary allusions abound, to everybody from Dante to Eliot to Mary Shelley to Joseph Conrad. I did hit on a couple of problems, one of which involves hissing the unhissable: "'What do you want?' Moon hissed."
Somewhere about page 300, things started getting out of hand. What had seemed eccentric and fun went so far over the top that it because outrageous. My guess is, you're either going to suck it up and go with it, or you'll throw the book down to show your displeasure. I went with it, but I still don't know what to make of it. Maybe you will.
One thing: Every advance review I read (and there were quite a few) referred to this book as being set in the Victorian Era. But it's made clear several times that Victoria's dead and a man is on the throne. Wouldn't that make the setting Edwardian? Or am I missing something?