An interesting if deeply flawed film, Knickerbocker Holiday is a musical comedy with rather deeper things on its mind, including political corruption, the definitions of patriotism and democracy, and the stubborn individualism at the root of Americanism. That it attempts to deal with these ideas is laudable; unfortunately, its handling of them is rather hit-and-miss, with the result that Knickerbocker promises much more than it delivers. It does boast three excellent songs from the original stage production, including the incomparable "September Song," and sharp eared listeners can hear another of the show's best songs, "It Never Was You," used as underscoring. The songs added for the film don't rank with these Kurt Weill classics, but they're quite pleasant and have that unmistakable Jule Styne sprightliness to them. Nelson Eddy's big baritone is put to good use in six numbers, but the demands put on his dramatic talent are much too taxing. Charles Coburn certainly has less voice but more ability, and gives out with a lovely and touching "September Song," and Constance Dowling is appropriately vivacious. Harry Joe Brown's direction is adequate, but rather is required to bolster the film's assets and disguise its shortcomings.