Kathy H, one of the clones in Ishiguro's 2005 novel, Never Let Me Go, is sentimentally attached to an old song she remembers from a tape she owned at school but lost. She used to dance round the dormitory singing the lyrics, “Baby, baby, never let me go”, while hugging a pillow and imagining the baby she'd never have. As adults, Kathy and her friend Tommy search junkshops together until they finally find a copy of that tape. Tommy loves Kathy so much that their improbable victory is almost spoilt: she saw the tape before he did, and he'd wanted so much to find it for her.

Never Let Me Go provides a harrowing, but hauntingly beautiful account of the human condition: it missed the Booker but deserved an even greater prize. For the past four years a big question in the literary world has been, “What next from Ishiguro?” The answer turns out to be a set of quizzical and restrained Nocturnes - five gentle mood pieces about music and nightfall.

Once again, the music in question is what purists think of as trash. In the first story, Crooner, an East European guitar player working in Venice explains: “What tourists can't take too much of is the classical stuff, all these instrumental versions of famous arias. OK, this is San Marco, they don't want the latest pop hits. But every few minutes they want something they recognise, maybe an old Julie Andrews number or the theme from a famous movie.” The guitarist recognises his mother's favourite singer, Tony Gardner, in the crowd and is drawn into helping him to serenade his wife after dark. The guitarist accompanies Tony for a couple of numbers in the gondola and afterwards the sound of Lindy Gardner sobbing in her hotel room is only just audible above the slapping water.

Lindy Gardner reappears in Nocturne, where she is in another hotel, recovering from the facelift she's had after her amicable divorce from Tony. Here she attempts to befriend Steve, a saxophone player, whose agent and former wife have talked him into having a facelift too. The bandaged pair go on night-raids in the hotel, frightening the security guards. Their surreal short-lived friendship illuminates the commonplace call Steve places to his former wife: “I said, ‘I love you', in that fast, routine way you say it at the end of a call with a spouse. There was silence of a few seconds, then she said it back, in the same routine way. Then she was gone. God knows what that meant.”

All five stories have unreliable male narrators and are written in the first person. The effect is one familiar from Ishiguro's recent novels: an intimate, or confessional, tone that is also deliberately casual. Some critics regret the transition Ishiguro has made from the beautifully crafted sentences of his earlier books, to this chatty, almost “Dear Diary” style of writing. Taste differs, but by now it is clear that this exquisite stylist is serious in his pursuit of a minimal - perhaps even universal - mode of expression for the emotional experiences that define our lives as human.

Nocturnes is a set of poised and playful reflections on the falling away of sentiment: the sadness at the end of the day, or at the death of a friendship or love affair. The trials of ageing are softly focused. Some characters fight superficially with a surgeon's scalpel, but there is no evading the real tragedy of mortality, wasted opportunities and diffusely receding dreams.

Ishiguro brings his wacky and idiosyncratic sense of humour to bear on these dark subjects. In Come Rain or Shine an old friend and house guest finds himself talked into making dog-smell soup to save a failing marriage: “Perhaps it was simply the effect of receiving a clear set of instructions, however dubious: when I put the phone down, a detached, business-like mood had come over me. I went into the kitchen and switched on the lights.”

In Malvern Hills an idealistic and as yet unsuccessful young songwriter is told at a failed audition: “No offence, mate. It's just that there are so many wankers going around writing songs.”

The final story, Cellist, returns to a band of musicians in the piazza of an Italian-seeming city. The narrator is a band member reminiscing about Tibor, a fellow player. Tibor, a young Hungarian cellist, was befriended by a mysterious woman in her forties, claiming to be a virtuoso and offering professional advice. During their friendship it emerges that this woman hadn't played the cello since she was 11 because she couldn't find a good enough teacher and didn't want to “damage her gift”. Tibor's friend reports that, after weeks of deception, “he felt no resentment, only a hunger to understand her as fully as possible”. In contrast to the intense friendship between Tibor and the older woman, the friendship between the band members is almost familial. But there is a sad note that sounds inside the conviviality: “The bosom pals of today become lost strangers tomorrow, scattered across Europe, playing The Godfather theme or Autumn Leaves in squares and cafés you'll never visit.”

These stories recall Ishiguro's best known novel, The Remains of the Day. In their surreal touches they resonate with The Unconsoled. And in their deceptively simple exploration of love and loss, they build on the achievement of Never let Me Go. After reading them, it is impossible not to return to the same question: “What next from Ishiguro?”

Nocturnes: Five Stories of Music and Nightfall by Kazuo Ishiguro
Faber & Faber, £14.99; 240pp Buy the book

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