After a food spill ruins the haute couture fashion she's supposed to model at an elegant charity soiree, ex-shopgirl Irene O'Dare (Anna Neagle) puts on a vintage blue gown that belonged to her late mother. The dress - showcased in a rich Technicolor sequence becomes a sensation. So does lrene when the buzz goes round the party that she's a royal heiress. Her shop manager, eager to exploit the gossip and sell more dresses, adds to the illusion by putting her up at a Park Avenue address. But lrene's would-be Prince Charming (Ray Milland), who knows her secret, isn't fond of the charade. This charming, gossamer- winged tale of Cinderella wish fulfilment originates from the 1919 stage hit that for two decades held the Broadway record for most performances. The Dandridge Sisters, including the pre-stardom Dorothy Dandridge, are in the film's jubilant, Harlem-based "Alice Blue Gown" song-and-dance sequence.