Once close high school friends in a small town, Toru and Naoko stumble into each other on a crowded Tokyo train and quickly revive their friendship. They share a certain intimacy that neither has managed to recreate with any one of their new classmates or dorm mates who know nothing about the tragedy of their past. The renewal of their friendship, however, does not help them to move forward. While together trying to overcome the sadness of their adolescence, Toru and Naoko find their grasp on the present-day spinning out of control. Toru, the narrator, recounts how, on Naoko's birthday he felt "There was something strange about Naoko's becoming twenty. I felt as if the only thing that made sense, whether for Naoko or for me, was to keep going back and forth between eighteen and nineteen. After eighteen would come nineteen, and after nineteen, eighteen. Of course. But she turned twenty. And in the fall, I would do the same. Only the dead stay seventeen forever."

This duty also informs his first non-fiction volume, Underground. Murakami became obsessed with the 1995 Tokyo subway attack, in which Aum cult members released Sarin nerve gas on five separate trains. The book consists largely of edited transcripts of interviews conducted with survivors or relatives of victims. "How on earth did this happen to us?" one woman asks. "That 'How on earth...?' ", Murakami comments, "stuck in my head like a big question mark." No wonder: it is also the cry of pain that fires the depths of his fiction.

Finding oneself down a well, or otherwise underground, is an oddly charged possibility in Murakami. The well can furnish a kind of metaphysical holiday - the narrator of Murakami's masterpiece to date, The Wind-Up Bird Chronicle, seeks out a well bottom in order to "think about reality". Alternatively, as Naoko fears in Norwegian Wood, being down a well might mean suffering in despair, being swallowed up by madness, inexorably dying. The horror of the Tokyo subway shares this motif with Murakami's fiction: as one survivor tells him: "The fear of going underground in a metal box and something bad happening is overpowering."

Such is the exquisite, gossamer construction of Murakami's writing that everything he chooses to describe trembles with symbolic possibility: a shirt on a washing-line, a string of paper cut-outs, a butterfly hairslide. Three times in the novel Watanabe reaches out to clutch light: first a sparkling mote of dust, next a firefly disappearing into the night. The third time he is strolling in the sanatorium gardens and becomes transfixed by Naoko's lit window in the distance, "like the final pulse of a soul's dying embers". You cannot retain the fleeting after-image of a firefly - similarly, perhaps, you cannot keep such embers alight by force of will. Maybe this bird, as John Lennon sang, has flown.

For all its metaphysical gloom, however, Norwegian Wood also flutters with sympathetic comedy. What on first glance appear to be bathetic lapses into jovial innuendo or irrelevant cookery chat between characters make the point that people in real life do not react to alarming or tragic situations in consistent or appropriate ways. Underground 's testimonies reflect the same truth - some survivors are angry, some scared, others calm or even lighthearted.