The setting of AD Miller's second novel is a world away from the drug-fuelled, snow-bound streets of corruption-filled Moscow depicted in Snowdrops, his Man Booker shortlisted first novel.

Opening in sunny, drug-free California in the summer of 1993, Miller's story follows the decades-long friendship of two Englishmen, Adam Tayler and Neil Collins, who first meet at a beach hostel in San Diego.

Miller compares the shifting moods, one-upmanship and petty jealousies to a courtship as they share an off-beat sense of humour, perform a karaoke duet of Take it Easy, and swim in the warm Pacific at midnight. Still in their early twenties, both are defined by their upbringing. At first, Neil is insecure. On a short break between jobs he is provoked by Adam's mild questioning about his future plans (he thinks Adam is suffering from "the tyranny of vocation among well-bred graduates... the idealism that someone else was always paying for"), while Adam is oblivious and naïve, enjoying a gap after graduation before making a decision about his career.

They agree to deliver a "driveaway" to San Francisco, but stop off on the way to take in the sights, and they join a disparate group of tourists to visit Yosemite National Park. It is here that they see the Faithful Couple, a natural phenomenon in the Mariposa Grove in Yosemite National Park: two giant sequoias fused together into a massive tree trunk at their base, separating into individual trees the higher they stretch toward sunlight: "they only existed together, in their rivalrous embrace".

Adam and Neil are photographed in front of it, posing in mock dispute. It is here, too, that Miller's "faithful couple" become fused through an event with far-reaching consequences for both of them when the edgy competitive streak fuelling their friendship weakens their moral compasses. "In California the lies they told felt almost true. Or, if not true, at least possible, as if Neil might plausibly be someone new if he and his new friend willed it." Of course, there's a girl at the core of this male-focused story. Her absence constitutes a presence in their shared secret history.

The faithful couple conceit is good but the idea doesn't need to be repeated so frequently. Miller is more effective when he zooms into particular details in order to represent upheaval. "Churches turning into flats, cinemas transforming into gyms, old boozers mutating into restaurants: the abracadabra of money, magicking everything into something else, a shape-shifting spell that was evidently too strong for megaterrorism or the imminent war to disrupt."

However, he needlessly yokes Adam and Neil's chosen careers to the economic and social climate of each decade, and it seems unlikely that they would keep in touch long after 1993. Adam joins the Civil Service and works on immigration cases for the Home Office, later moving into consultancy work on Neil's (bad) advice, while Neil enters business with a dot.com enterprise called HappyFamilies, moves on to the London property market, and swiftly into hedge funds. The guilt they thought they'd left behind at Yosemite, though, resonates through their see-sawing fortunes, seeping out only as each begins to consider the moral consequences in light of subsequent experience.

If The Faithful Couple is Beaches for blokes, The Winter War, by Finnish-Swedish author Philip Teir, could be an ironic version of Neil's HappyFamilies.com. In Teir's clever first novel, two things are certain from the outset: sociology professor Max Paul will divorce, and the hamster, crushed underfoot in the slapstick opening scene, will reappear at an inconvenient moment.

Originally published in Swedish under the subtitle "A Novel About Marriage", the story revolves around the Paul family of Helsinki: Max, nearing his sixtieth birthday, is working on his magnum opus, a revisionist biography of Edvard Westermarck; Katriina, his wife, is depressed in her HR job at a local hospital; eldest daughter Helen, a teacher, is struggling with control issues; and Eva, a 29 year-old eternal student, is in London deciding what she wants from life.

Katriina battles insomnia and Max spends his nights trawling internet forums looking for opportunities to link to his own articles now that his ideas are outmoded. He eagerly accepts an invitation from Laura Lampela, a former student-turned-journalist, to interview him for a feature about his work. At the ego-deflating suggestion of his editor, though, Laura reads his manuscript, and a number of comic misunderstandings ensue, enlivened with playful nods to Westermarck's theories on marriage, happiness and morality. Teir keeps tight control over the shifting family dynamics, exposing the messy interconnectedness of their individual lives: "life consisted of a series of disparate embarrassments and episodic intervals that didn't necessarily add up to a coherent whole".

Two historical wars frame the story's chronology: the Winter War of 1939-40, when the small Finnish army held the Mannerheim Line against advancing Soviet Union troops, and the summer war of 1808, when the Czarist army captured territory from Sweden along Finland's �sterbotten province. It is no coincidence that Max is originally from �sterbotten, and Katriina's roots are in Czarist Russia. Helen is teaching Linna's novel, The Unknown Soldier (the Finnish recaptured territory from the Soviets in the Continuation War of 1941-44), and Eva visits the front line of the Occupy movement outside St Paul's cathedral. While it's a cliché that marriage is a battlefield, Teir's slanted view of family dynamics is inventive, solidly crafted and highly entertaining.