Teresa Wright plays Charlie, a small-town high-schooler who enjoys a symbiotic relationship with her favorite uncle, also named Charlie (Joseph Cotten). When young Charlie "wills" that old Charlie pay a visit to her family, her wish comes true. Uncle Charlie is his usual charming self, but he seems a bit secretive and reserved at times. Too, his manner of speaking is curiously unsettling, especially when he brings up the subject of rich widows, whom he characterizes as "swine." When a pair of detectives (MacDonald Carey and Wallace Ford), posing as magazine writers, arrive in town and begin asking questions about Uncle Charlie, young Charlie's curiosity is aroused. Why, for example, has Uncle Charlie torn an article out of the evening newspaper? Rushing to the library, Young Charlie locates the missing item: the headline screams WHO IS THE MERRY WIDOW MURDERER? As the horrified Charlie reads on, the conclusion is inescapable: her beloved Uncle Charlie is a mass murderer, preying upon wealthy old women. And what happens next? Thornton Wilder, Sally Benson, and Alma Reville (Mrs. Hitchcock) based their screenplay on a story by Gordon McDowell, who in turn was inspired by real-life "Merry Widow Murderer" Earle Leonard Nelson. The casting, from stars to bit players, is impeccable; the best of the batch is Hume Cronyn, making his film debut as a wimpy murder-mystery aficionado. Lensed on location in Santa Rosa, California, The Shadow of a Doubt wasAlfred Hitchcock's favorite film.
~ Hal Erickson, All Movie Guide