Twenty-three years ago, Maggie D'arcy's family received a call from the Dublin police. Her cousin Erin has been missing for several days. Maggie herself spent weeks in Ireland, trying to track Erin's movements, working beside the police. But it was to no avail: No trace of her was ever found. The experience inspired Maggie to become a cop. Now, back on Long Island, more than 20 years have passed. Maggie is a detective and a divorced mother of a teenager. When the Gardaí call to say that Erin's scarf has been found and another young woman has gone missing, Maggie returns to Ireland.

Rough-around-the-edges Harriet Morrow has long been drawn to the idea of whizzing around the city on her bicycle as a professional detective, solving crimes for a living without having to take a husband. She seizes the chance when the prestigious Prescott Agency hires her as its first woman operative. The move sparks controversy—with skeptical male colleagues, a high-strung office secretary, and her boss, Mr. Theodore Prescott, all waiting for her to unravel under the pressure.

A hurricane is building, threatening the coastal town of Bois Sauvage, Mississippi, and Esch's father is growing concerned. A hard drinker, largely absent, he doesn't show concern for much else. Esch and her three brothers are stocking food, but there isn't much to save. Lately, Esch can't keep down what food she gets; she's 14 and pregnant. Her brother Skeetah is sneaking scraps for his prized pitbull's new litter, dying one by one in the dirt. Meanwhile, brothers Randall and Junior try to stake their claim in a family long on child's play and short on parenting.

In 1938, a dead whale washes up on the shores of remote Welsh island. For Manod, who has spent her whole life on the island, it feels like both a portent of doom and a symbol of what may lie beyond the island's shores. A young woman living with her father and her sister (to whom she has reluctantly but devotedly become a mother following the death of their own mother years prior), Manod can't shake her welling desire to explore life beyond the beautiful yet blisteringly harsh islands that her hardscrabble family has called home for generations.

Both a gripping locked room mystery, and a transporting, evocative portrait of a woman in crisis, Trouble Island marks the enthralling standalone suspense debut from Sharon Short, promising to be her breakout novel, inspired by a real island in Lake Erie, and true events from her own rich family history.