Every Vow You Break by Peter Swanson

After a drunken one-night stand before her wedding, Abigail Baskin tries to put the mistake behind her during a lavish, off-the-grid island honeymoon with her wealthy new husband. When the stranger from that night appears on the island insisting they’re meant to be, her unease escalates into terror as she uncovers a sinister, male-only conspiracy and realizes she’s being hunted. With escape nearly impossible and trust in short supply, she must outwit a circle of predators to survive.

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