Lucy Harper still has traumatic memories and lingering health problems from the 2020 pandemic. So, when a new virus surfaces years later, she and her husband, Reed, seek refuge on his family's private island off the coast of Maine. As Lucy uncovers Reed's family secrets and the island's history as a quarantine hospital for typhus patients, she becomes obsessed with the past and feels her own grip on reality slipping. Is the island haunted by the dead? Or is someone amongst the living taking their revenge?