Laura Cumming’s wonderful, haunting new book slips between genres. It is not quite a memoir, not quite a biography and not straightforwardly an investigation into the past. But this ambiguity fits the nature of its subject: what Cumming explores in this book, which is ostensibly an account of the early life of her mother, is the unreliability of memory itself. It is a poetic study in half-lights and fragments made up of shadowy bits of emotional bric-a-brac, tiny pieces in the jigsaw of a single life.

It’s an intensely visual narrative – as one would expect from Cumming, The Observer’s art critic. She probes constantly the meaning of an image. Those black and white photographs from long ago, for example: what do we learn from that picture of a father and child on a