But when Isobel, the daughter of the wealthy Anglo-Dutch engineering contractor responsible for building the island's fortifications, is found dead at the bottom of a bunker shaft, Lentsch sets out, with the aid of the local police chief, to discover whodunit. German soldiers, resentful of Lentsch's liaison with the island's most eligible young flapper? Islanders, outraged at Isobel's horizontal collaboration? Or one of the nameless army of slave labourers who carry out the fortification works under inhuman conditions for Isobel's father?
The solution turns out to be more prosaic. Along the way, however, Tim Binding draws on the relationships between Germans and locals, occupiers and occupied, to elaborate his central theme: the nature of collaboration in war and the moral accommodations we make in order to survive.
Ned Luscombe, the police chief malgre lui, has to implement German orders while obsessed by memories of a fling with Isobel. The bank manager and his daughter run a sex ring with German sentries. The local aristo, Mrs Hallivand, enjoys dinners a deux with the cultivated Lentsch. Zepernick uses his sexual conquests to further his career.
Equally, the willing local gals - "Jerrybags", as they were termed - scheme to "catch" a German officer and thus improve their social standing (and get a bit of sugar off the ration). There is, indeed, an inordinate amount of bonking in this book.
One problem with the historical novel is that it invites reviewers to look for inaccuracies. While Binding has evidently done his research, there are plenty here. For instance, though he properly depicts a Henschel engine pulling wagons along the sea front, he calls it a "Hirschel"; the Germans use the local post and banking systems, where in fact they had their own; and so on.
But this is a novel, not a history, and such solecisms will not offend most readers. Rather worse are the stylistic infelicities. Binding does not have the greatest ear for dialogue, and especially not for the rhythms of the Guernsey idiom. Most of the locals end up sounding like Ealing comedy mockneys, while the German officers, even when talking among themselves, are too often rendered in clipped sub-Colditz Englisch.
Again, this would not matter excessively were it not that the narrative moves mainly - in between the rumpy-pumpy - through interior monologue and reported speech. And it has the related effect that characterisation tends to be implausibly thin. The German officers come across as beer- swilling dullards, icily efficient ideologues or wistful sophisticates: all good stereotypes, but not the stuff of original drama.
Binding's theme is a compelling one, but his treatment of it suffers because these just aren't believable people facing credible dilemmas, prompted by comprehensible motives. It is absurd to expect of a historical novel that it be accurate in every detail, but it must be a viable version of the truth; something that could perhaps have happened. Island Madness is not it.