AÑO UÑA chronicles the impossible romance between Molly, a twenty-one year old American, and Diego, a Mexican in the throes of puberty. Molly travels to Mexico where she rents a room in Diego's house. A close relationship immediately develops between the two. Diego, who had previously been consumed by desire for his cousin, Emilia, redirects his obsession after Molly arrives. Molly enjoys Diego's flirtations, finding the attention and respect missing from her relationships with boyfriends back in the U.S. The relationship continues to grow until Molly returns to New York. Diego decides to run away and win her heart.