In July 1940, a ship containing 125 Oxford children and 25 of their mothers left Liverpool for America. They would spend the war as guests of Yale University, lodging with local families and so avoiding the bombs. Was it coincidence, though, that many of these children were the gifted offspring of Britain's academic elite? Cambridge had rejected Yale's invitation, concerned that accepting it might be "interpreted as privilege for a special class". Why did Oxford have no such qualms?

In his fourth thriller under the name Sam Bourne, Jonathan Freedland invests the scheme with nefarious intent; though of course, it's a while before the reader knows of its existence. We think James Zennor's wife Florence has abandoned him, taking their son Harry with her, because living with him has become unendurable: his violent rages and depressive episodes, not to mention his apparent carelessness as a father, leaving Harry alone beside a boiling kettle 

An experimental psychologist, James met biologist Florence in Barcelona at the People's Olympiad in 1936, where she was due to compete as a swimmer. After the civil war forced the event's cancellation he stayed in Spain to fight the fascists. But his status as a prime physical specimen to rival lithe Florence was altered for ever when a bullet shattered his shoulder in an escapade that also saw him witness the horrible death of his best friend. When we first meet him in Oxford four years later, James is in the grip of a paralysing post-traumatic malaise.

The early chapters take their atmospheric cue from Robert Harris's Enigma, which also showed us wartime through the prism of a damaged sociopath. But where Harris's maths genius Tom Jericho was a wet blanket unsuited to any activity but moping, James is driven by a righteous fury which he vents on anyone and everyone. His anger makes him blundering and unsubtle: excellent qualities in the hero of a thriller because, well, he could do anything  and does, despite his handicap.

And James's physical and psychological shortcomings serve another purpose. Bourne's subject here is eugenics, specifically the ideological affinities between the Nazis and those on the progressive left who believed that, as George Bernard Shaw wrote, "the only fundamental and possible socialism is the socialisation of the selective breeding of man".

James travels to Yale because he discovers that Florence and Harry have been evacuated there. What he uncovers  abetted, naturally, by a femme fatale journalist  is horrific, and tempting to write off as fantasy. And yet it is rooted in fact. Eugenics was in vogue at Yale, which, along with several other Ivy League universities, participated in a bizarre experiment to prove that "physique equals destiny" by photographing students naked with metal pins taped to their backs.

Bourne works these notorious "posture photos" into his plot, and there's a funny scene where James has a clandestine meeting in a pizza restaurant with a Yale official who has some of them in his bag. After grappling with his margherita  "the best introduction to the dish for a novice"  James catches a glimpse of one of a naked man and worries he has been targeted by a predatory homosexual: "It wasn't the first time James had encountered one of Lund's type."

James's love for his son is told rather than shown, and as a result feels too abstract to be a driving force. Still, Pantheon is a propulsive, satisfying novel which burns with moral indignation, earning Bourne his place at the thriller-writers' high table.

John O'Connell's The Baskerville Legacy is published by Short Books.

One autumn afternoon in the mid-60s, Ron Rosenbaum, a recently arrived freshman at Yale, was summoned to the university's Payne Whitney gym and instructed by a group of men in crisp white coats to strip off. They then attached large metal plates to his spine, placed him against a wall and took a series of photographs. He was told this "posture photo" was a routine part of the freshman induction process, intended to identify students whose weak posture needed remedial work.

Rosenbaum was not alone. For at least three decades, this procedure was standard practice at most Ivy League universities  George Bush Sr went through it at Yale. Nor was it confined to male students: Meryl Streep was photographed at Vassar, Hillary Clinton at Wellesley College, before the practice was discontinued in the late 1960s.

Three decades later, it emerged that the posture photographs were part of an elaborate programme, devised by respected scientists who believed that "physique equals destiny", to identify the most eugenically sound individuals in America and encourage them to breed together.

It is surprising that the "Great Ivy League nude posture photo scandal" (as the New York Times called it) has only now found its way into fiction. In Sam Bourne's ingeniously constructed Pantheon, the goings-on at Yale are connected to weightier events in the second world war. Its hero, James Zennor, an Oxford don traumatised by his experiences in the Spanish civil war, returns from an early morning row on the Thames in the summer of 1940 to find his beautiful wife, Florence, and young son, Harry, have disappeared. He then learns that they have fled to America, part of the exodus across the Atlantic by the rich and the well-connected when it looked likely that the Germans would invade. James follows them to Yale and there uncovers a pro-Nazi plot led by the dean himself, who also has eugenic designs on Florence's perfect body.

Meanwhile, a parallel narrative has Taylor Hastings, a cypher clerk at the US embassy in London, handing over to British fascist sympathisers copies of cables showing Roosevelt manoeuvring to bring the US into the war on the British side, documents that, if revealed to the American press, could lose FDR the upcoming election. Events come to a climax in a well-orchestrated chase in Washington DC.

These days, successful journalists seem compelled to take up fiction. "Sam Bourne"  the distinguished Guardian columnist Jonathan Freedland  is already an old hand, with four thrillers and sales of more than a million under his belt. His readers will not be disappointed by Pantheon, a businesslike page-turner, which maintains the tension well and has a strong sense of place; the contrast between rationed and blacked-out Oxford and the faux medieval abundance of New Haven, Connecticut is especially well done.

It is, though, interesting to compare Freedland's book with William Boyd's Restless, another British thriller set in America in 1940 as the struggle between isolation and intervention intensifies. Whereas a storyteller such as Boyd expresses the battle of ideas through human character and behaviour, Freedland is too impatient to use the indirect approach and unwilling to trust his readers with the complexities of history. He evidently feels they can only approach the past with the assumptions and attitudes of today. So, when it comes to trauma, we get modern post-traumatic stress disorder, not 1940s war neurosis; and when it comes to eugenics, a subject now inescapably linked to the Holocaust, we get crude stereotypes.

Freedland invents an improbable scene where Dr Zennor is shocked to find in the Yale library a volume made up of pro-eugenic statements by all the deities of the British progressive left  Keynes, Beveridge, Shaw, Wells, Harold Laski, JBS Haldane and so on. Are we to believe that an Oxford psychologist married to a biologist would have been unaware of this? More likely, he would have been a eugenicist himself. A historian or fiction writer would have wanted to know why.

Mind you, Freedland could simply have stuck to the historical record. In 1937, James Zennor's real-life equivalent, the Oxford psychologist William Brown, astonished the British scientific community by publicly hailing Hitler as the "greatest psychotherapist of the nations". Dr Brown was a renowned therapist and had been a highly effective shell shock doctor in the Great War, using hypnosis to help soldiers relive their traumatic memories; Wilfred Owen called him "a wizard who mesmerises at will".

Only in 1940 could Brown reveal that his pro-German remarks had been intended to pave the way to a private audience with the Führer, in the course of which he had hoped to bring his old hypnotic skills to bear and transform the German leader into a reasonable man.

Evidently he did not succeed.

Ben Shephard is the author of The Long Road Home: The Aftermath of the Second World War (Vintage)