Literary types like to dismiss genre fiction as pure formula, yet judging by the number of published novels that are near- (or all too frequently far-) misses, a detective novel is as difficult to write well as any other.

I was musing on this after reading C.J. Sansom's Dark Fire, the second in what looks likely to be a long series featuring a hunchback lawyer, Matthew Shardlake, who's navigating the hazardous political/religious waters of the later years of Henry VIII's reign with Cromwell (no, the other one) as his patron.

Having enjoyed the first in the series, Dissolution, I was keen to pick up this one, but finished it feeling vaguely dissatisfied (although I did read it through in one session, so it was good enough).

Analysing why, I decided that Sansom has got it 75 percent right. The characters are excellent—Matthew is an interesting, complex central figure, with believable sensitivities about his hunchback and a plausible back-story, and there are colourful minor characters, particularly the apothecary Moor who is his best friend and, in this second book, an important character.

The historical setting is, so far as I can tell, well researched, and it only occasionally intrudes in a way that suggests the author couldn't resist including this detail, without literary reason.

The plots too fairly rolic along, in a way that demands you keep reading, and have the sort of neatness and fairness that fiction demands and real life almost never delivers. (So in Dark Fire, an orphan girl who is accused of murder is kept safe and finally, rightly freed, when anyone who knows anything about "justice" of the time knows she wouldn't have had a hope. But fair enough: our 21st-century minds demand right triumph, in a way that would have been seen as hopelessly naive in the 16th century.)

What isn't right is the language, and the detail of the writing. "Lay off the weather!" I feel like yelling at Sansom at regular intervals. And he hasn't really got the "show not tell" rule; e.g. in Dissolution: "As I passed down Ludgate Hill, I noticed a stall brimming with apples and pears and, feeling hungry, dismounted to buy some." Drop the "feeling hungry", please. Why else would you?