It’s a sentence that may spin in your mind while you read the opening pages of “Wave,” Sonali Deraniyagala’s devastating new memoir. If hers is not the saddest story I’ve ever heard, it’s the saddest I ever want to hear again. This book opens beneath you like a sinkhole.  Ms. Deraniyagala is an economist, originally from Sri Lanka, who teaches at the University of London and at Columbia. On the day after Christmas in 2004, she and her family were staying at a beach hotel on Sri Lanka’s southern coast. That’s the day, the world now knows, that an earthquake spawned a tsunami in the Indian Ocean.  The author saw it, or rather she saw something, coming. “Come out,” she said to her husband, Steve, who was in the bathroom. “I want to show you something odd.” The ocean looked closer. It looked foamier.  Before long they and their two young sons were running. There was no time to warn her parents, staying in the same hotel. The four of them made it into a Jeep, and were driving away, when the tsunami overtook them.  Her husband died in the churning water. So did their sons, ages 5 and 7. So, it happens, did her parents. The Jeep turned over on Ms. Deraniyagala, nearly crushing and drowning her. She survived, miraculously, by clinging to a tree limb.  “Wave” is a granular, tactile working through of grief, regret and survivor’s guilt. It maintains a tight focus. Don’t arrive here looking for statistics and a journalistic overview of the tsunami. This book contains nothing about tectonic plates, the pressure per inch of water or the numbers of the dead.  It’s a somber volume that suggests that Julian Barnes was right about grief, when he wrote in “Flaubert’s Parrot” that you don’t emerge from it cleanly, as if from a tunnel into sunshine. “You come out of it as a gull comes out of an oil slick,” he wrote. “You are tarred and feathered for life.”  About her family, Ms. Deraniyagala thinks to herself: “When I had them, they were my pride, and now that I’ve lost them, I am full of shame. I was doomed all along, I am marked, there must be something very wrong about me.”  She continues: “Why else did we have to be right there just when the wave hit? Why else have I become this shocking story, this wild statistical outlier? Or I speculated that I must have been a mass murderer in a previous life, I was paying for that now.”  The first sections of “Wave” are largely about her plans for suicide. “I’ll wait until all the bodies are found,” she says. “Then I will kill myself.” Her friends and family hide the kitchen knives. They keep watch over her for months.  Ms. Deraniyagala is a close observer of her own anger, more deranging than purifying. When she spies a sobbing and apparently orphaned boy in the aftermath of the tsunami, she reports: “I didn’t try to comfort him. Stop blubbing, I thought, shut up. You only survived because you are fat.” About her own skinny sons, she adds: “Vik and Malli didn’t have a chance.”  Her malice can be glittering. Here’s her internal monologue when a woman on an airplane asks her about her family: “Oh shut up, you nosy cow, I think. You will probably faint if I tell you. You’ll have to pull down your oxygen mask.”  Anger is a downward chute into something approaching madness. Ms. Deraniyagala begins to haunt and harass the members of the Dutch family that has moved into her parents’ old house in Sri Lanka. Sometimes fueled by vodka and Ambien, she rings their doorbell at 2 a.m. and makes deranged phone calls. She debates killing herself by smashing her car into the wall in front of the house.  Ms. Deraniyagala soaks in guilt about her own survival. She feels guilty, too, that she mourns her husband and children more deeply than she does her parents. “How hideous,” she says, “that there should be a pecking order in my grief.”  The dark places in “Wave” are made bearable, to some degree, by the author’s gift for evoking her life before everything changed. There are memories of her childhood in Colombo, Sri Lanka’s capital, and of meeting her husband at Cambridge University. She recalls him grilling fish while listening to John Coltrane. She remembers his obsession with cricket, and that he did an excellent Elvis Costello impression, singing the song “Alison.” He told her that Alison was an anagram for her own name, Sonali.  Then there’s this on the way her son Vik almost vindictively ate potato chips, junk food she usually forbade: “He took a single crisp out of the pack, savored it with his eyes, lowered it into his mouth, and munched,” she writes. “With unhurried, exaggerated actions to demonstrate just how much he relished them.”  Stories of grief, like stories of love, are of permanent literary interest when done well. I’m not convinced that Ms. Deraniyagala is a great writer — I would not rush to read her on any topic — but a form of greatness reverberates from her simple and supple prose here.  Her slim book moves forward in time, about a year per chapter. It intimately circles the question all memoirs of grief must pose, one that she puts this way: “Who am I now?”  Ms. Deraniyagala’s great realization, a full seven years after the tsunami, is not that her grief has diminished. It remains raw to the touch. Even the sound of footsteps in the apartment above hers makes her think that her boys are still playing upstairs. “Then I have to accept,” she writes, “that I don’t have them.”  Her great realization, she says, is that “I can only recover myself when I keep them near. If I distance myself from them, and their absence, I am fractured. I am left feeling I’ve blundered into a stranger’s life.”  Ms. Deraniyagala would never use a bogus word like “healing.” Her book is therapeutic because it isn’t therapeutic at all.
Sonali Deraniyagala chronicles the agonized aftermath of the 2004 tsunami that drowned her parents, husband and two children.