Sinister shadows abound in McMahon's supernatural thriller about two sisters, a haunted pool, and a legacy of wishes and sacrifice. As a child, Jackie was often overshadowed by her dazzling older sister. Everything seemed to come easier to Lexie--adventure, friendship, even the love of their family--until, as a teenager, she began to manifest symptoms of "schizoaffective disorder of the bipolar type." The two girls continued to grow apart; Jackie escaped to the West Coast for college and career. Now their grandmother has died, leaving Lexie her house, Sparrow Crest. Jackie, a social worker, distances herself from her sister for her own mental health, so when Lexie leaves her several manic messages one evening, Jackie ignores the calls only to hear from her aunt the next morning that Lexie is dead, drowned in Sparrow Crest's pool. Jackie flies back to Vermont and discovers that Lexie was documenting strange occurrences that seemed to center around the pool, which is fed by a mineral spring. Her research into the family history, as well as other deaths by drowning, sparks Jackie's dread and interest, and she begins to look more deeply into the truth about their family, Sparrow Crest, and the pool that is the dark heart of it all. McMahon alternates chapters about Jackie with chapters about a woman named Ethel Monroe and her husband, Will, who stayed at the springs in 1929 when they were on the grounds of a swanky hotel and who made a secret wish. Like many, Ethel soon realizes that the springs offer both hope and tragedy, and her story becomes interwoven with Jackie's investigations. McMahon has a gift for creating creepy atmosphere and letting spooky suggestions linger in the mind. She's also adept at weaving legends and stories into the fabric of what feels like real life, because her characters are so believably vulnerable. For best results, read it on a dark and stormy night--in a well-lit room, far away from the water. Copyright (c) Kirkus Reviews, used with permission.

Social worker Jax is exasperated when she sees nine missed calls on her phone from troublesome older sister Lexie, then horrified to learn that Lexie has drowned in the pool at their grandmother's estate. Lexie was investigating the estate's past, which turns out to be darker than the family imagined. From the author of the New York Times best-selling The Winter People; with a 75,000-copy first printing.

Tired mental health stereotypes and a dispiriting ending mar McMahon's latest taut supernatural thriller (after The Invited). Jackie Metcalf has worked hard to distance herself from her family, especially after her grandmother left her Vermont estate to Jackie's mercurial sister, Lexie. When Lexie drowns in the house's pool--just as their aunt had decades before--everyone suspects she took her own life, but Jackie soon learns the situation is much more complicated. Interwoven with this contemporary story line is one beginning in 1929: 37-year-old Ethel Monroe struggles with infertility, but finds hope in stories of the healing powers of a natural spring attached to a Vermont hotel, despite locals' warnings about the spring's dark powers. McMahon's skills in crafting captivating plots and building suspense shine as the connection between the two threads slowly becomes clear, but the story ends with more fizzle than bang. More disappointing is the way the challenges and traumas of complex mental illnesses are flattened into mere annoyances; Lexie, who has bipolar disorder, is broadly painted as a manic, flaky artist, and her struggles are portrayed primarily through the effect they have had on Jackie's life. Still, readers who prioritize atmosphere and intricate plots will be engaged. Agent: Daniel Lazar, Writers House. (Apr.)

Jax, a clinical social worker, has convinced herself that estrangement from her older sister, Lexi, is a boundary-setting necessity, completely unrelated to Jax's jealousy over Lexi inheriting Sparrow Crest, their family home. But when Lexi drowns in Sparrow Crest's spring-fed pool, Jax is overcome with regret that she ignored Lexi's desperate phone calls the night she died. Lexi's house is littered with notes chronicling her obsessive investigation into local legends warning that the pool's healing miracles are repaid with the spirits of those it lures to their deaths. As she works through the evidence of Lexi's final days, Jax tries to trust her clinical mind when it tells her that sleep deprivation is creating the hair-raising sounds of Lexi's voice and the glimpses she sees of a strange woman lounging poolside. But then she discovers an unsettling connection between Lexi's death and the Jazz Age resort whose ruins are buried beneath Sparrow Crest. A streamlined supernatural thriller built on gifted storytelling and the atmosphere of a fireside ghost tale, woven with strands of longing and regret.