If Coralie Sardie had lived another life, in another time and place, she might have become a champion swimmer, a lauded athlete with garlands crowning her head, surrounded by crowds who pleaded for her autograph after she crossed the channel from England to France or circled Manhattan Island. Instead, she swam in the Hudson as dusk crossed the horizon, making certain to keep to the shadows. If she were a fish, she would have been an eel, a dark flash secreted within the even darker water, a lone creature set on a journey northward, unable to stop or rest until her destination had been reached. On this raw night in March, she stepped out of the river when she could swim no more, shaking from exertion. The relay swimming title had just been granted to a fellow from the New York Athletic club who’d been dubbed the Human Fish, but Coralie could have beaten his time with ease. She climbed onto a deserted bank under a sky swirling with stars and stood ankle-deep in the mud. She wrung out her hair, a smile playing at her blue lips. This had been her longest swim thus far. She’d lasted ninety minutes in the frigid river, a personal record. A wind had picked up and the weather was raw; few swimmers would have been able to last in the murk of the rushing water. All the same, Coralie was no champion; she had no clock and no admirers. She wore men’s clothes that made her movements easier, fitted trousers and a white shirt tucked into her waistband. Before dressing she coated her limbs with bear grease mixed with digitalis, a concoction meant to act as a stimulant and keep her warm. Still, despite this elixir and her training to withstand inhuman circumstances, she shuddered with the cold.