The cops in this case are a special team of street-wise detectives and an arrogantly annoying psychologist led by the plodding Mitchell Wa. At times it seems like anybody who has ever made a career fighting crime wants in on this case, only to fall over themselves bolting for the exits when they do. Not exactly a cast of thousands, but a goodly number nevertheless. The reason is that Kelln has devised an interesting twist on the serial-criminal oeuvre. Our baddie earns a high profile seemingly by infecting the mind of anyone left alone in a room with him. Not just the women he rapes, but the cops, nurses and doctors who watch over him once he's captured.

Okay, the darkness that seeps from within is a metaphor for the evil that finds a comfortable home in a succession of characters, mainly by recalling their own sins. Lost Sanity still suffers from the characteristic weakness of this sub-genre of the police procedural, itself a sub-genre. Once it is established that the bad guy is something beyond human, the only thing to keep us reading is to up the weird and grisly ante as we go.

"Enough already," the reader cries, "I get the point."

Or maybe not. If you're more inclined to say "Bring it on, how weird can it get," then you should enjoy Lost Sanity.