1928. Famed Chinese magician Wei Ling Soo, arguably the most admired man in his profession, is on a successful European tour. What the public does not know is that underneath his make-up and Chinoiserie, he is really Caucasian Stanley Crawford (Colin Firth) of England. Stanley is a man of science, he believing that everything, like his illusions, can be explained logically. As such, he is an avowed atheist. Because of his non-belief of concepts such as faith, he is also a largely emotionless man. Howard Burkan (Simon McBurney), Stanley's childhood friend and a magician in his own right, asks him for a favor: help him expose a young American woman named Sophie Baker (Emma Stone) acting as a psychic and medium. Sophie and her mother (Marcia Gay Harden), who are from a poor background, have infiltrated the wealthy Catledge family of the French Riviera. The Bakers have been able to bilk money from the Catledges in their belief in what Sophie has told them. While the Catledge daughter Caroline (Erica Leerhsen) and her husband George (Jeremy Shamos) believe Sophie is a fake, the Catledge son Brice (Hamish Linklater) and the family matriarch Grace (Jackie Weaver) want to bring Sophie into their lives permanently, Grace, who wants to set up a foundation for Sophie, and Brice who wants to marry her. In observing Sophie's abilities, Howard, a skeptic, admits that he was unable to explain how Sophie was able to do the things that happened, such as making certain items levitate, and that she knew things that there is no way she could have known. Stanley is glad to oblige Howard's request, he often exposes mediums in his steadfast belief that there is no such thing as psychic ability. Stanley hopes to visit with his Aunt Vanessa (Dame Eileen Atkins), the woman who largely raised him, while he is doing this work for Howard. She lives in Provence and is arguably his favorite person in the world. In Stanley and Sophie meeting at the Catledge home, Sophie knows, based on his outward disdain toward her, that he is there to question her abilities. Stanley, conversely, admits to himself that time after time he cannot explain how Sophie does or knows what she does or knows. Regardless, he largely holds steadfast to his belief about her. But as Stanley spends more time with Aunt Vanessa and Sophie, he may come to a realization that a little unexplained phenomenon may actually make him a happier man.