I read the first hundred pages of [SS-GB] with mounting enthusiasm. The action was plausible, the characterisation firm and the surveying intelligence adult and well-informed….

Deighton is good on insignia, badges of rank, uniforms, military protocol. He is especially good on German inter-service rivalries and has clearly researched them exhaustively. If the Germans had come to London, then doubtless the Gestapo, the regular Wehrmacht, the SD, the Abwehr, the SS, the Geheime Feldpolizei and all the rest would have jostled and quarrelled in something like this way.

But, of course, they didn't come to London. And from about Page 100, the subversive thought kept surfacing: what is the point of this kind of historical 'might have been'? It has, of course, been used in the past to make some significant historical or metaphysical statement. But if there was any such intention here I failed to spot it….

Much of the action concerns, as already suggested, jockeying amongst the Germans for seniority. And here, I suppose, one of the troubles of this 'let's suppose' technique makes itself felt. While the broad strokes are fine and constitute an exciting backdrop for a tale of intrigue and adventure, the detailed sociopolitical analysis of a situation that never existed gets a bit wearisome. Its only real value is to establish a spurious authenticity, which admittedly it does effectively, but it clogs the action….

But my deepest reservations stem from another source. They are analogous to those aroused by watching synthetic television drama, run-of-the-mill movies, processed West End farces and so on, the feeling that the work is using you rather than collaborating with you. The purpose behind SS-GB, which becomes increasingly clear, is not to explore reality, expand consciousness, generate beauty or reveal truth but to keep the paying customers happy…. One senses behind Len Deighton's book research and engineering but not true creative impulse. It is well-written, in places strikingly well-written, but never profound or lyrical because, of course, any literary qualities would flaw its glossy surface.