It is advertised on the jacket of the book, in an approving quote from Roddy Doyle (not just clever but spectacular, he opines). It is surely present in the very title. Either you know that 419 is the number of a Nigerian statute that prohibits phishing emails from those claiming, for instance, to be the hard-up offspring of a betrayed diplomat, and that the figure is becoming slang for any sort of betrayal in the global lexicon, or you don't. Ferguson is in no hurry to tell you, although he will - in the voice of a briefly introduced police detective called David Saul who flits as quickly out of the narrative - on page 111.
419 is, without doubt, a very clever book. If you are the sort of busy, wary person who just punches the delete key whenever any dangerous spam materialises in your inbox - surely the action of any sane person - it may never have crossed your mind that there might be a good story in these plainly fictitious appeals.
Ferguson takes us deep into the murky world of the 419ers in Nigeria, and the tragedy that befalls a dysfunctional Canadian family as a result of an old man's gullibility.
There is nothing superficial about his research, which not only unravels the criminal underworld of the African state and the corrupt society of which internet scamming is only a small part, but is authoritative about how that dovetails with Western interests in the oil industry, the environmental damage being done and the victimhood of the people there.
Our heroine is Laura, daughter of the man whose death at the start of the book is revealed as a desperate and failed last throw of the insurance-loaded dice, after being suckered by an appealing (supposedly female) pitch.
She is an editor, so her detective work involves analysing the distinctive errors in the English grammar and vocabulary of her father's correspondent so that she can track down the culprit.
As in all the best 'tec tales, however, there is no-one else she can trust, although the accident-investigating detective, Sergeant Matthew Brisebois, wishes it was he. She must deceive the authorities both at home and in Africa to find her own truth.
Running parallel with this main narrative is the story of wandering girl Amina of the Sahel and a native fisherman, Nnamdi, who will find each other, but also tragedy, when their story begins to intersect with that of Laura and Winston, the Nigerian wide-boy behind the scam.
Yes, Ferguson's book is clever alright, and its interweaved narrative, split into four elemental sections - Snow, Sand, Fuel and Fire - is well constructed and compelling. But every few pages something will pull you up short. It might be a cliched chapter end ("She fell into sleep, like a body down a well."), or a self-consciously "modern" one ("But by then it was too late. Far. Too. Late."), or Laura's use of Cluedo characters (Colonel Mustard, Miss Scarlet) as successful aliases. More often it is the paragraph of research work that the author has been too pleased with to disguise more effectively, like the biblical David Saul appearing with the true word on 419, or a political analysis of the rape of the Nigerian delta by the oilmen.
The economic wisdom is, in some ways, the best thing about the book. Sadly none of the characters is more than superficially drawn, Laura something of a cypher, and Winston rarely more than his clothes. The complexity of the story-telling is not quite enough without characters whose fate you need to share in.
419 is certainly as clever as it thinks it is, but it is not clever enough to stop showing off and be a thoroughly well-conceived piece of work.