Sarah Sullivan is forced to live all winter in an isolated mountain cabin with a total stranger. Sarah Sullivan leaves home to marry her fiancé in Fort Laramie, Wyoming, although she has not seen him in a year. In route, the stagecoach is robbed and one of the passengers is killed, leaving a small child, Penny, who becomes Sarah's responsibility. Seth Jenkins, a trapper living on a mountain, witnesses the robbery and scares the bandits away. He carries the woman and child to his mountain cabin and takes care of them until they're able to travel. As he prepares to take them down the mountain to Fort Laramie, an explosion blocks the main pathway, trapping them for months. Sarah works beside the mountain man and Penny to survive the cruel winter months, and the attraction for each other grows. Her fiancé is waiting on her arrival, but can she marry one man when her heart is trapped by another?