Instructions for a Heatwave

Set during a severe heatwave and drought in London in the summer of 1976, the novel follows the Riordan family across five days as they search for their missing patriarch and confront the secrets that have fractured their relationships.

On a scorching Thursday morning in July, Gretta Riordan, an Irish immigrant from Galway who has lived in London for decades, bakes soda bread in her kitchen on Gillerton Road in Highbury, as she has done three times a week throughout her life with Robert. Her husband Robert, a quiet, recently retired bank worker, goes out to buy the newspaper. He does not return. Hours pass. Gretta goes outside, looks up and down the empty street, and calls his name.

The narrative shifts among the three adult Riordan children, each section revealing their present lives and buried pasts. Michael Francis, the eldest, is a history teacher in his early thirties who loathes his job, having abandoned a PhD to support his family after getting his girlfriend Claire pregnant at university. Claire gave up her own history degree when they married. Now she has secretly enrolled in an Open University course, and Michael Francis struggles with her growing independence and the guilt of a brief affair with a colleague. When Gretta phones that evening, burying the alarming news that Robert has been gone eleven hours amid complaints about a lost shed key, Michael Francis grasps the situation and calls his sister Monica.

Monica, the middle child, lives in rural Gloucestershire with her second husband Peter, an antiques dealer, in the farmhouse Peter previously shared with Jenny, the mother of his daughters. Monica's day begins with the death of the family cat, which triggers buried memories of a traumatic miscarriage during her first marriage to Joe. The miscarriage was not accidental: Monica terminated the pregnancy herself. Her younger sister Aoife was at the hospital and seemed to recognize the truth. Joe left soon after, and Monica has believed for years that Aoife told him. Their relationship collapsed entirely after a confrontation at a family gathering, during which Monica accused Aoife of being a nightmare baby who destroyed Gretta's health. Aoife later tried to make amends, but Peter shut the door in her face. The sisters have not spoken for years. When Michael Francis reaches Monica, he tells her Robert has withdrawn money, possibly taken his passport, and vanished.

In New York, the youngest sibling, Aoife, carries a secret she has hidden from everyone: She cannot read. She experiences text as letters that rearrange and dissolve, a condition never diagnosed during her chaotic schooling. She failed every exam except art, was held back twice, and left school without qualifications. She works as an unpaid assistant to the photographer Evelyn Nemetov and moonlights at a music club in the Bowery. Her central crisis is a growing blue file stuffed with contracts and invoices she cannot process. Her lover, Gabe, a Vietnam War draft dodger working as a sous chef, has asked her to move in, but she refuses, fearing he would discover her secret. Michael Francis calls to tell Aoife their father is missing and that she needs to come home.

Aoife arrives at Gillerton Road at dawn on Friday. Gretta is characteristically critical, commenting on Aoife's hair. Michael Francis joins them, and the three settle into familiar patterns of bickering and avoidance. Aoife phones Gabe from a phone box. His voice is flat: He has found the blue file, which contained contracts and thousands of dollars in uncashed checks. He is upset and disappointed. Monica arrives later and swerves past Aoife without acknowledgment, as if Aoife does not exist.

Michael Francis shows his sisters a torn scrap of paper found under the kitchen cupboard, bearing the words "and they say the end is coming" in unfamiliar handwriting on a fragment of an Irish-stamped envelope. Monica presents a more concrete discovery from Robert's locked desk: check stubs showing monthly payments of twenty pounds to an unknown payee named "Assumpta," going back years. The siblings agree to search for clues without telling Gretta. Aoife confronts Monica, demanding to know if Monica accused her of telling Joe about the terminated pregnancy. Monica admits she has believed this for years; Aoife swears she never told him. Michael Francis also confesses to Aoife about his affair with Gina Mayhew, a biology teacher. On a school trip to France, they slept together once. Claire discovered the affair when she called the hostel after their son Hughie was injured and was told Michael Francis was not in his room. Aoife responds with pragmatic sympathy, calling it a mistake, not a catastrophe.

Early Saturday morning, Gretta receives a phone call from a cousin's wife in Connemara, a rural region in western Ireland, reporting that Robert has been seen near Roundstone, coming out of a convent. Gretta becomes agitated and mentions the name "Frankie" before falling silent. Aoife is furious to learn for the first time that Robert had a brother named Frankie, supposedly killed during the Troubles, the decades-long conflict in Northern Ireland. The family presses Gretta, and under sustained questioning she reveals the story. Robert, born Ronan, and his brother Francis, called Frankie, both fell in love with a girl named Sarah. Sarah married Robert, but the day after the wedding she ran off with Frankie. Robert searched for them in vain, then went to fight in World War II. Frankie later surfaced in an Ulster prison, convicted of shooting a police officer. After Frankie's release, Robert secretly arranged for him to be cared for at the Servite Convent of St. Assumpta near Roundstone, sending money every month, though the brothers never spoke again. Gretta learned all of this not from Robert but from a priest she met in Galway.

Aoife then asks whether Gretta and Robert are actually married. Gretta's silence confirms they are not. Robert proposed but said they could not marry yet. Gretta, already pregnant with Michael Francis, could not return to Ireland in shame. Robert gave her a ring, they posed for a photograph, and Gretta told her family they were wed. Over the decades, the fiction became indistinguishable from truth. Monica is furious at the hypocrisy, given that Gretta once shamed her for sleeping with Joe before marriage.

On Sunday, the family takes the night ferry to Cork and drives to Connemara. On the ferry, Aoife realizes she has not had a period since April and understands she is pregnant. Gretta goes to the convent alone and finds Frankie bedridden and dying, shocked by how much he resembles Robert. Robert is not there. Gretta tends to Frankie and leaves a message telling Robert where the family is staying. On Mannin Bay beach, Claire tells Michael Francis she has not slept with anyone else but says he is free to leave, tired of his resentment about his abandoned academic career. She will finish her degree and support herself.

The family settles into a cottage Gretta inherited on Omey Island, a tidal island off the Connemara coast. That night, Aoife runs barefoot across the causeway at low tide to a phone box and calls Gabe. For the first time in her life, she tells another person she has a problem with reading. Gabe responds with quiet recognition, saying his grandfather had the same difficulty. He has sorted out the entire blue file. She tells him she wants them to live in the cottage together.

Monica waits for Aoife at a wall on the island, and they walk back together. Monica apologizes for the terrible things she said years ago and for believing Aoife told Joe. Aoife tells Monica she is pregnant, and Monica is deeply moved. She privately realizes she is not going back to Gloucestershire. The sisters fall asleep side by side. The next morning, the family breakfasts in the garden. Hughie spots a figure coming across the causeway, walking toward them with a stooped gait and a hand raised in greeting. Gretta opens the gate and confirms it is Robert, returning to them at last.