Suzy is the film in which Cary Grant, overcome by the beauty and vivacity of Jean Harlow, sings her a love ballad! This lighthearted moment aside, Suzy, adapted from a novel by Herbert Gorman is a standard-issue love triangle, set against the tapestry of World War I. Harlow plays a London showgirl, married to Irish engineer Franchot Tone. When foreign spy Benita Hume shoots Tone, mistaking him as a threat against her mission, the terrified Harlow flees into the night, certain that she will be accused of her husband's murder. After the war breaks out, Harlow, believing herself a widow, falls in love with handsome aviator Cary Grant. She marries the well-bred but irresponsible young ace, only to discover that Tone has not been killed after all! This being an idealized World War I film, somebody is going to end up sacrificing his/her life on behalf of somebody else, but we're not about to reveal any more.
~ Hal Erickson, All Movie Guide