Regarded by many critics as Alfred Hitchcock's best American film, Shadow of a Doubt certainly displays the master of suspense thrillers in top form. Mixing doubt and fear with ordinary small-town life, Hitchcock keeps his audience off balance throughout the film. The story is set in the town of Santa Rosa, California, and the film was largely shot there. Such use of location shooting was not a usual practice in the 1940's, but in Shadow of a Doubt the contrast between the placid, conventional life in the town and the twisted mind of Uncle Charlie Oakley (Joseph Cotten) is definitely aided by the real setting.
The film portrays throughout the theme of the affinity between Uncle Charlie and his niece Charlie (Teresa Wright), who is named after him. The niece feels that the presence of her uncle is what the family needs to get it out of its rut, and she decides to telegraph him, only to find that he has just telegraphed the family himself. Young Charlie is delighted with this example of what she sees as telepathy and keeps stressing to her uncle that they are closer than uncle and niece. As the plot progresses, however, she begins to fear their closeness. At first she gleefully tells him that he cannot hide anything from her, but by the middle of the film she wishes he could. Instead of being kindred spirits, the two Charlies turn out to be opposites—the good and evil parts of the same personality.
There is, of course, suspense and mystery in Shadow of a Doubt. The mystery is not, however, who committed the crime but rather what crime was committed. As the first half of the film progresses, we grow more and more certain that Uncle Charlie is a criminal, but we have no idea what his crime is. It is. not until a suspenseful scene in which the niece rushes to the library to find a newspaper article that she learns that her uncle is the so-called Merry Widow murderer, a man who has been murdering rich widows for their money. Before this is discovered, however, we have reason to become increasingly suspicious of him. The first time he appears he is in a furnished room with a great deal of money lying about, and when his landlady tells him two men want to see him, he decides to escape from them by visiting his sister and her family in Santa Rosa.
In Santa Rosa, Uncle Charlie at first seems to be a personable, successful individual, but he becomes unreasonably upset when he thinks people are trying to find out about him. After the library scene, the mystery and suspense change. Now the questions center on what Uncle Charlie will do (he has already met a rich widow in Santa Rosa), whether the detectives will find him out, and what young Charlie will do with her information. Young Charlie does not feel she can turn in her own uncle, especially since she believes that it would kill her mother to find out that her younger brother is a murderer. Once Uncle Charlie realizes that she knows of his guilt and even has a ring which connects him with the murders, young Charlie's life is in danger.
Hitchcock makes a point of contrasting the large city with the small town. Before we see Uncle Charlie, we see establishing shots of the city in which he lives; then, as we hear him say "Santa Rosa" on the telephone, we see establishing shots of that quiet town. Indeed, Hitchcock chose Thornton Wilder as the principal screenwriter for the film because of his splendid evocation of small-town life in his play Our Town. It is ironic, then, that in finding something to lift the family out of its rut, young Charlie gets more than she bargains for. It is almost as if the film is suggesting that to have excitement you have to have danger or decadence also. In fact, Uncle Charlie himself, though he is part of the problem, decries cities and modern life.
Under the opening credits we see couples in old-fashioned dress waltzing to "The Merry Widow" This scene is inserted or superimposed several times during the film, but it is not until we see it immediately after young Charlie finds the article about the Merry Widow murderer that we realize its significance. In a sense, the music has a dual meaning which reflects the distorted mind of Uncle Charlie. He frequently says that the modern world is corrupt, a "foul city" he calls it, and contrasts it with his romanticized idea of the past.Thus the "Merry Widow" dancers represent both the idealized past and the grotesque situation of the present.
The film is filled with other deft Hitchcock touches besides the motif of the dancers. The affinity of the uncle and niece is brought out by the fact that each is first shown in profile lying on a bed. The scene in which Uncle Charlie tries to kill young Charlie by shutting her in a garage where a car's motor is running is ironically set up by a previous scene in which Graham proposes to young Charlie in the same garage. The pace of the film is also carefully controlled, with some scenes being deliberately slowed down. After the telegraph office calls the family about Uncle Charlie's message, for example, it takes them an inordinately long time to find out what the message is. When young Charlie decides to go to the library, however, the pace accelerates and the tension increases; she has only a few minutes to reach the library before closing time, and we see shots of her rushing through the streets heedless of the traffic; of the town clock showing the time; and of the library lights being turned out just as she arrives. After she manages to get in—despite the protestations of a stereotyped old-maid librarian—and finds the damning information, the camera pulls back for a long shot from above which dissolves into the shot of the "Merry Widow" dancers. After the quick and exciting editing of the scene on the train in which uncle and niece struggle until the uncle falls in front of a speeding locomotive, Hitchcock slows down the pace for the ironic ending at the funeral. Graham and young Charlie, who are the only ones who knout the truth, listen to the service as Uncle Charlie is eulogized. The last words in the film are "the sweetness of their characters live on forever."
Joseph Cotten and Teresa Wright as the uncle and niece contribute excellent performances which give vitality to the conception of their like but opposite personalities. Cotten is able to convey the surface charm which almost covers the menace within, and Wright convincingly shows us a naive young woman who finds herself in a situation she could not imagine, much less suspect. The others in the cast are adequate, including Henry Travers and Hume Cronyn as Charlie's father and his friend, who both read pulp mystery stories and continually talk about murder while they are unaware that a real murderer is right under their noses.
Shadow of a Doubt is vintage Hitchcock. From the overall conception to the smallest detail, the imprint of this master filmmaker is evident.
When the detectives drop the case because they think another man is the murderer, the danger to young Charlie increases, since she is now the only threat to her uncle. After surviving two "accidents" which are clearly murder attempts by Uncle Charlie, she finally persuades him to leave town by threatening to turn her evidence over to the police. When she boards the train to see him off, he again tries to kill her; they struggle, and finally he falls into the path of a speeding train. The film ends with Uncle Charlie's funeral. He is eulogized, and only young Charlie and Detective Jack Graham (Macdonald Carey), with whom she has fallen in love, know the true story.