If Berlin Game introduced us to Bernard Samson and the murky world of Cold War espionage, Mexico Set takes that world and makes it considerably more uncomfortable. The second book in Len Deighton’s Game, Set and Match trilogy builds on the intrigue of its predecessor, deepening the personal complications while reminding us that in the intelligence business, knowing whom to trust is often the hardest part of the job. It is another thoroughly enjoyable spy thriller, full of double-dealing, political manoeuvring and the nagging suspicion that somebody, somewhere, knows rather more than they are letting on.

One of the things I enjoy most about Samson is that he remains refreshingly human in a profession that demands a rather unnatural relationship with the truth. He has the experience to recognise when something doesn’t quite add up, but that doesn’t mean he can always work out what is really happening. I like his dry humour, his scepticism and his tendency to view the grand schemes of his superiors with a mixture of professional resignation and barely concealed irritation. He is not the sort of hero who charges into a room with all the answers. Instead, he muddles through, trying to make sense of incomplete information while wondering whether the people giving him instructions have his best interests at heart.

In Mexico Set, that uncertainty becomes particularly important. The story continues to explore the possibility of betrayal within British intelligence, with Samson caught between his professional responsibilities and relationships that make his job much more complicated than it ought to be. Deighton is very good at making apparently straightforward developments feel suspicious. A conversation can leave you with more questions than answers, and a seemingly sensible decision may look rather different once another piece of information comes to light. I found myself trying to work things out alongside Samson, never entirely certain whether my suspicions were justified or whether I was being led down the wrong path.

The personal dimension is especially effective. Samson’s relationships are not simply a distraction from the espionage plot; they are part of what makes the whole business so difficult. Trust is already a scarce commodity in his professional life, and the prospect of having to apply the same suspicion to people he cares about gives the story an added emotional weight. I find Samson more interesting because he cannot simply switch off his feelings and become the perfectly detached intelligence officer his profession might seem to require. His judgement is shaped by experience, loyalty and personal history, which makes him believable even when he gets things wrong.

The Cold War setting provides plenty of material for Deighton’s social and political commentary. This is a world in which ideological differences justify extraordinary levels of secrecy, manipulation and interference. Both sides are playing for advantage, and neither is particularly interested in allowing inconvenient truths to get in the way of national objectives. The supposed moral clarity of the conflict looks decidedly less convincing when viewed from inside the intelligence services. What matters is often not whether an action is right, but whether it works, who benefits and how much damage can be kept out of public view.

I particularly like the attention Deighton gives to the bureaucracy surrounding espionage. Intelligence officers have to contend with internal rivalries, competing priorities and superiors who may be more concerned with protecting their own reputations than discovering the truth. It makes the world feel less like a glamorous adventure and more like an office where the paperwork happens to involve international security and the occasional betrayal.

Of course, the novel has aged in places. Its technology and communications belong firmly to another era, and the intricacies of the plot sometimes require a little concentration to keep track of who knows what. There are moments when the political background and exposition slow the pace, too. Readers looking for constant action may find Deighton’s more measured approach frustrating, but I think the gradual accumulation of information is one of the story’s strengths.

Ultimately, Mexico Set is a very worthy continuation of the trilogy. It develops Samson as a character while delivering the twists, suspicion and political intrigue that make this series so enjoyable. Some of the details may feel dated, but the underlying questions about loyalty, institutional self-interest and the cost of living a life built around deception remain relevant.

I’m certainly still on Samson’s side, even when I’m not entirely convinced he has worked everything out. That, for me, is the mark of a good espionage thriller, and Deighton has once again delivered a cracking read. Now, on to London Match.

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