Do novelists need credentials? Once, almost a century ago, the vogue for hard-boiled fiction meant that in the masculine Hemingway hegemony then holding sway, novelists needed to be graduates of the ‘University of Life’. Writers, it was argued, had to spend their apprenticeship riding the rails, tending bar in tough-guy saloons and doing almost any work that could be described as manual labour.

This changed postwar, with greater affluence and millions more people in higher education, including women. Among them were a growing number taking postgraduate degrees in creative writing – most famously at the Iowa Writers’ Workshop, but followed quite credibly in this country at the University of East Anglia.

What, then, to make of a writer who flouts these conventions, appearing with a first novel at the age of 65, without a university degree or any DEI affiliations? An Old Etonian, moreover, who has spent 20 years in the army, followed by ten as an equerry and private secretary to the royal family? All I can say is that Jamie Lowther-Pinkerton’s When Love and Loyalty Collide (Bantam, £16.99) defeated all my cynical expectations. It is a very good read – intelligently structured, well-written and candid when candour is called for (there are many violent scenes and a few explicit sexual encounters).

Danger is in the air, and the BBC brings news every day of an increasingly perilous world

The story has two protagonists, male and female. The heroine, Missie Ormesby, is English, but she grew up in India speaking fluent German, thanks to her German governess. She is strong-willed and impetuous, and ends up being sent to Le Rosier, a finishing school in the Swiss Alps. Life there is generally cossetted, but in 1938 danger is in the air, and the BBC brings the girls news each day of an increasingly perilous world.

At Le Rosier, Missie becomes friends with a German girl, Anna Friedrich, and is introduced to the Friedrich family in Munich. After she fails to rebuff the aggressive sexual advances of Anna’s brother, Franz, she is saved only by the intervention of Franz’s friend, the anti-Nazi Conrad von Echlau. When, next day, Conrad quarrels on the street with a group of hostile Brownshirts, Missie returns the favour and saves him from a potentially lethal beating.

The connection between Missie and Conrad is immediate and strong, and the two soon become lovers. But Conrad recognises that their differing nationalities mean that their love affair can only be tenuous, and reluctantly Missie sees this too: ‘There was no hope. There never had been, not with the way the world was headed.’ Faced with the certainty of heartbreak, Conrad breaks off the relationship.

The book then jumps to the wartime of 1940. Drafted into the Luftwaffe, Conrad is involved in a plan to destroy the British radar defences that are thwarting the German air attacks. Meanwhile, in England, Missie is conscripted, thanks to her fluent German, and sent to Bletchley Park to help the Enigma decoding efforts. As a result of an indiscreet slip by the Germans, Missie and her colleagues uncover a plot to land troops near the British radar headquarters at Bawdsey in Suffolk – one that involves Conrad.

This is not a novel full of surprises, and for most of it we await what seems the inevitable convergence of Missie and Conrad’s respective efforts. But the wait is never burdensome and the story never flags. The author manages to convey often highly detailed information, even of a military sort, in a way that is always clear and often illuminating. He says he has used his mother’s activities in the war as the basis for his story, but he has also clearly done a tremendous amount of research and handles everything – from the topography of the Suffolk coast near Shingle Street to the interior decoration of Göring’s palatial hunting lodge – with the assurance of an accomplished veteran novelist. The only question remaining after such a strong debut is what Lowther-Pinkerton will write next.

The narrative of Mad Mabel (Macmillan, £16.99), by Sally Hepworth, is related by an 81-year-old woman who lives on a quiet street in Melbourne. A little cranky and very strong-willed, Mabel nonetheless gets along with her neighbours fairly well – with the exception of her nemesis, Ishaan, and his ‘deranged chihuahua’. When Ishaan drops dead in his kitchen, word somehow gets out that Mabel is not the innocent old lady she appears but a convicted murderer who has done time.

It takes the length of the book before it’s confirmed that she is indeed a murderer, as well as identifying who she has killed and why. But the humour and zest of the narrative means the deferral is painless; and we also learn of several other deaths involving her as her story unspools.

We are now so accustomed to unreliable narrators that it takes some time to recognise that Mabel, in her account of her life, is in all but one respect as straight as a die – unlike the other characters who constitute the attractively wacky but credible cast. They include her lifelong best friend Daphne, who provides the largest surprise; Pete the Greek, who has ties to Mabel which only gradually emerge; the litigious Joan, whom Mabel tries to avoid; and the seven-year-old Persephone, an obnoxious, precocious child, who gradually works her way into Mabel’s heart. The narrative alternates between a potted history of Mabel’s past and the ongoing events of life on her street. The book is part comedy, part thriller and entirely engaging.

No. 1 St James’s Park (Scribner UK, £20) is Alan Judd’s second novel in a planned series of historical espionage thrillers set initially during the first world war. It can be profitably read on its own, but we have a richer sense of Judd’s heroine, Emily Grey, from reading both books.

Here Grey is working on secondment in a hut in St James’s Park when she is summoned to MI6’s Whitehall headquarters. An agent in Bern, nicknamed Fritz the Ritz, has information on German industrial production that is potentially of considerable value. But the officer in charge of running him has been exposed and therefore withdrawn by the British – who now need Grey (a fluent German speaker) to take over until a permanent officer can be found.

Once in Switzerland, Grey quickly discovers that Fritz the Ritz is peddling information that could easily be culled from published sources, and that in some cases he has simply made things up. His exposure results in other discoveries, including a British embassy official who is selling classified information and blank British passports, and a couple (a British man named Rutland and his German wife) who want to help him do so. Grey has a sidekick, Nigel Nisbet, whom she finds annoying, though his keenness on her becomes apparent as the story progresses.

The writing throughout is unshowy but clear, and the descriptions are often sharpened by Judd’s sly sense of humour. There is a particularly funny scene when Grey masquerades as a poule de luxe (without much luxe) to keep Rutland from leaving the country.

Judd has shown himself a dab hand at virtually every kind of espionage fiction, and some may think it a pity that the historical genre does not make use of his deep knowledge of present-day spying. But this series shows an aptitude for research and a pleasing restraint in its application, while still giving an intimate sense of the settings of an earlier era. I look forward to further volumes featuring Emily Grey.