An alien spacecraft is shot down by the U.S. government, crashing into the Wisconsin countryside. The alien inside, taking on the human form of a young widow’s deceased husband using DNA from a lock of hair found in the home, embarks on a critical mission. Unfamiliar with human customs and the English language, the alien must navigate the complexities of human interactions and society. The widow, initially terrified and resistant, is forced into a reluctant partnership with her husband's lookalike. Together, they set out on a cross-country journey to reach a designated pickup location in Arizona, where the alien hopes to be rescued by his own kind.

Throughout their journey, the two protagonists encounter various obstacles, including government agents in hot pursuit, aiming to capture the alien for research purposes. Their time together forces the widow to deal with the grief of her husband's death and confront her feelings towards this alien doppelgänger. As they travel, the alien demonstrates an ability to learn quickly, adopting human behaviors and emotions, which draws the pair closer, evolving from mutual distrust to a deep, understanding bond. The expedition across the American landscape not only exposes the alien to the breadth of human life and culture but also serves as a healing process for the widow, reigniting her sense of hope and capacity for love.