The latest great American road story is written by a Mexican woman about one of the most terrible sources of Western shame of our age – the detaining and dehumanising of young children who cross borders in search of safety. The figure we know to be the biggest villain in this sorry saga is not mentioned by name – though, admittedly, neither are the four main characters in Lost Children Archive, though they converse, listen to music and audiobooks, read each other stories and make them up on their long journey from their home in New York City to the bad borderlands at the southern edge of North America.

The ‘archive’ of the title alludes to a project undertaken by the unnamed narrator of the novel’s first half, who sets off with a car full of recording equipment and written and photographic ephemera in search of the untold stories of the border children. More specifically, she has resolved to find the missing children of her undocumented migrant neighbour Manuela. In the car is her husband, distant and increasingly estranged, as well as their two children, ‘the boy’ and ‘the girl’, whose guileless play and innocent questions simultaneously assuage and amplify the cynicism and fatigue of a marriage in decline.

Lost Children Archive is autofiction with a nonfiction twin – Tell Me How It Ends: An Essay in Forty Questions, Luiselli’s first effort to tell the stories of undocumented migrant children. It is informed by a journey she made (with her husband and two children) to Arizona in 2014 and her subsequent work as a courtroom translator for Salvadoran, Honduran and Guatemalan migrant children. At the novel’s heart is an interrogation of duty. Who owns a story and who tells it? Where does the writer’s remit end? Where does it begin? As in other works of autofiction (by Knausgaard, Heti, Kraus, Cusk, Laing), feelings of guilt and obligation feed the narrative tension. Here fault lines are transgressed and the stakes feel almost impossibly high.

The family stop to sleep at motels and eat at roadside restaurants. They make a detour to visit Geronimo’s grave and Graceland, feeling as they do the jarring strangeness of their trip. Is it work? Are they there to bear witness? To sightsee? As they drive (fully half of the book is taken up by the car journey) the narrator regards the children – the girl her own, the boy her husband’s, both from previous relationships – with a kind of prophetic horror, feeling a sense of loss even in their presence. The girl ‘sucks her thumb’ until ‘slowly she is absent, erased from us, slipping back deep into herself’. Inevitably, her mother’s thoughts are drawn outward:

I close my eyes and try to join my children in their sleep. But my mind twists and spirals down into the thought of children lost, other children who are lost, and I remember the two girls, alone, imagine them walking across the desert, possibly not too far from here.

This is the work of the novel, the uncomfortable folding together of our own lives and ‘the news’: it’s something happening out there, until we can imagine it happening to us, to our children. The text is piecemeal; conversations repeat themselves or fail to resolve; details are omitted. It is littered with quoted fragments from Lord of the Flies and the writings of Andrzejewski, Eliot, Pound, Rilke and Sontag. There is a set of stories within the story, called ‘Elegies for Lost Children’, written by an invention of Luiselli, an Italian writer named Ella Camposanto, that feature glimpses of migrant children leaping boxcars and crossing deserts. A sort of bibliography emerges, in the form of the inventories of the boxes the family have brought with them in the car. These contain transcripts of sound recordings, migrant mortality reports, maps, photographs and news clippings.

When the narration is taken up by the boy, the effect of the changed voice is disorienting, and the careful work of the first half – the project, the politics – falls away as we slip into the mind of a child. Lost Children Archive isn’t an easy read. Nor, I suspect, does the author believe it should be – it is resistant, harrowing and highly allusive. Whether it meets the challenge Luiselli sets for herself I am not yet sure. It is nonetheless engrossing, a novel of great skill and certainty, even as it asks uncertain questions, ones to which it is becoming increasingly pressing that we find answers.