The Midnight Swimmer, By Edward Wilson

Killing is always a serious matter. All too often, amid the glitzy gadgetry of the spy thriller, all the fast cars and sexual adventures, we lose sight of the essential seriousness of what is at stake.

John le Carré reminds us, often, and so does Edward Wilson. And Wilson has the advantage that he has chosen to play with hindsight and backstory in his trilogy of thrillers. In this third, the ominously named Catesby, a secondary figure in earlier books, takes centre-stage. We have survived Catesby's adventures, but might not have done.

This book is set in the early 1960s. We first see Catesby and his duplicitous boss, Henry Bone, disposing of an inconvenient American in a manner we recognise as tradecraft from its similarities to what has been alleged about the death of Dr David Kelly. They operate in the murky area where intelligence gathering and occasional murder overlap with deniable backdoor diplomacy, in an era where humanity's future is at stake because the US thinks of statesmanship as poker and the Russians think of it as chess.

Wilson has a nicely measured taste for historical irony and plausible conspiracy theory. This novel about what turns into the Cuban Missile Crisis is full of sidelights on the Profumo Affair, the French Connection and precisely why Marilyn Monroe sang "Happy Birthday" to JFK. Catesby is a perpetual outsider – alienated from the Norfolk fishermen among whom he grew up, but not quite one of the mandarin class. Like all outsiders, he is forced constantly to observe and notice, purely to survive.

This is an intellectually commanding thriller which does well those things that thrillers are supposed to do, but adds a mordant wit, and a poignant sense of the human cost of every move in the game of nations. Wilson's characters move among historical personages – Che Guevara gets some memorable scenes, and Harold Macmillan has a powerful moment – but there is equality. Wilson takes the real and the imagined with equal high seriousness. We spend the book knowing that the world survives – but Wilson's characters do not have that luxury, and that makes us care for them.