Cheney Duvall travels from New Orleans to San Francisco, escorted by Shiloh Irons. In the St. Francis de Yerba Buena Hospital, Dr. Baird and most of the others treat her with respect, but she finds some of the medical personnel are doubtful of her character, her intent, and her skill. She must prove herself and assert her authority again and again. Outside the hospital walls, San Francisco teems with brothels, criminal gangs, and poverty-stricken vagrants and immigrants. The hospital has decreed that none of these people will receive treatment, and when Cheney fights to combat these prejudices, she finds that the only support she can count on is from Shiloh Irons. But when catastrophe suddenly strikes, even Cheney finds that none of her medical education has prepared her for an overwhelming disaster.