William Hastings steers a wagon train, known as The Donner Party, off course by promising a shorter route to California through the Sierra Nevada Mountains. After several early snowstorms, the emigrants and its leaders find themselves trapped, freezing and without any source of food. A small group is formed, nicknamed The Forlorn Hope, to try and reach California and organize a rescue party. The threat of death and imminent starvation dissolves the group's camaraderie as they are forced sacrifice one another as a source of nourishment. Surviving only on the flesh of the fallen members of their party, the remaining travelers must weigh their consciences against their will to survive.