The Saturday Big Tent Wedding Party BY Alexander McCall Smith Little, Brown, 248pp, £16.99
The successful serial novelist often has to meet a difficult, if not impossible, brief. "Write the same, but different," their publishers will urge. And they will retire to their study, wondering what on earth that can possibly mean.
By the 12th book in the series, most writers would have exhausted the possibilities of their fictional world. But Alexander McCall Smith's No 1 Ladies' Detective series - like its heroine, Mma Ramotswe herself - is made of far more robust stuff.
The reason, I think, is twofold. Firstly, McCall Smith realises the reassurance implicit in repetition. When Mma Makutsi enters, we know it is only going to be a matter of time before she refers to the fact that she passed her secretarial exams with an unprecedented mark of 97 per cent; just as we will be reminded of Mms Ramotswe's girth, or "traditional build" and the essential goodness of her husband Mr JLB Matekoni, who is always addressed with his honorofic and full set of initials alongside his surname.
These phrases turn the key of memory and make us recall just what else it was that we found reassuring about McCall Smith's fictional Botswana in the first place. Its decency, for one thing. When the scatterbrained, wildly impulsive apprentice mechanic Charlie becomes the reluctant father of twins, Mma Ramotswe's description of his girlfriend's family immediately tells us what we are to make of them. "They are good people, you see. They follow the old Botswana ways. They are polite."
Politeness, respect, forgiveness: these are the totems of McCall Smith's fiction. Everything about 21st-century society might seem to be conspiring to strip them away from us, but his Botswana novels are part of a valiant and humane rearguard action in their defence.
Only last week in 44 Scotland Street, one of his characters noted how rude we become when we think no-one is looking at us, when we are half-hidden behind the wheel of a car (road rage) or vituperatively responding to to someone else's opinions on the internet. Take away the restraint which is a necessary part of human interaction and, ultimately, we take away respect for others.
His Botswana novels tilt on a similar moral axis, a second factor in their appeal. That world may not be as technologically advanced as ours, but in some ways it is morally superior. The old Botswana ways - not perfect, because they also allow for primitive superstition - insist on respect and formality even when there is disagreement. ("You are right about many things," says Mma Ramotswe to her husband, "but you are not right about that.")
Her main case this time involves the night-time killing of cattle belonging to a former mining recruitment officer who now runs a small farm.We know he is a bad lot right from the start, when he refuses to tell her the name of his nearest village. But soon Mma Ramotswe finds herself facing a genuine moral dilemma as, in the process of solving the crime, she promises not to reveal its perpetrator. And concealing a crime is, of course, a crime in itself.
We know that Mma Ramotsw will solve the case, because that is what she does. We know that there will be a happy ending, and that Mma Makutsi will finally tie the knot with her one-footed husband Phuti, because that much is implicit in the title.
We know too, that for a few short hours, McCall Smith can be relied upon to take us to a land where life is lived with the requisite moral attentiveness and good humour. But for all his books' charm and reassurance, they can still surprise - and even move - the reader, often through the smallest of details. When, for example. Mma Makutsi snaps the heel of the shoes she has bought for her weddings, we are suddenly right in the middle of a fully engaging parable of pride and poverty.
"One or two people had witnessed the tragedy, or at least seen part of it: a young man passing by, a boy on a bicycle, an old man standing in the shade of a tree. But they had only seen a woman racing after a white van and stumbling; they had seen her bend down and change her footwear before walking off towards the main road. So might we fail to see the real sadness that lies behind the acts of others; so might we look at one of our fellow men going about his business and not know of the sorrow that he is feeling, the effort that he is making, the thing that he has lost."
So might we. But so might we all, also, realise life's joys too. Or at least that rather generous helping of them bestowed, in these novels, under Botswana's wide, cloudless, skies.