You’ll have to steel yourself to read Wave, but steel yourself you should, because this is one of those books – like The Year of Magical Thinking or The Diving Bell and the Butterfly – that tells you so much about grief and survival. And though it is about unthinkable loss, it is also the most touching love story. Wave is about what happened to Deraniyagala while on holiday in Sri Lanka on Boxing Day 2004, when – steel yourself right now just to read on – she lost her husband, two sons and both her parents in the tsunami. She herself was also swept up by the wave – the family were together mucking about with Christmas presents in their hotel room when it arrived – and her description of washing up in the mud, internally injured, naked from the waist down, spinning round and round, and slowly realising that she is the lone survivor of her family, is an astonishing piece of writing: clear, unsentimental, terrifying – a lesson in restraint and clarity. The rest of the book, ostensibly about having to live after losing her sons and husband – and parents, though as she herself admits, grief has a hierarchy – is also a most loving portrait of the life she had with them, in London, Colombo and Cambridge. This is a short book with not a spare word in it. Deraniyagala gets obsessed with suicide, goes mad, drinks and takes drugs after her tragedy, and it takes her two years to even set foot back in her family’s London house, but she does survive, and the insights and wisdom her survival offers is why this book must be read.