Maddie Duncan (Helen Mirren) is a timid thrift store employee. One day at work, she finds a pair of expensive looking high-heeled shoes in a box of donations. Upon fitting them, her personality changes and she becomes more confident and assertive. She storms out of the store and catches a cab to a mansion where she is strangely comfortable. When the maid asks who she is she claims that she is Susan Montgomery - the wife of Kyle Montgomery, a wealthy big city lawyer and the owner of the house. She then shares tales of the maid's life which a stranger could never know. She tells the maid she is having a bath and runs up to change. When Maddie takes the shoes off, she turns back into a timid girl. The maid proceeds to run her off, but once the shoes return to her feet Maddie regains the confidence and knowledge she had when she first entered the house.

When Kyle returns home, he finds Maddie sitting on his couch dressed in his dead wife's clothes. Maddie, as Susan, retells the events of her death, revealing how Kyle killed her. She then picks up a gun and begins shooting at him. After a bit of a chase, Maddie's feet begin to hurt. She takes off the shoes and returns to her usual personality. Panicking when she sees the gun in her hand, she suddenly drops it and dumps the shoes in a garbage can, running off in her stocking feet.

Afterwards, Kyle decides to close the house for the season, but not before telling the maid her services are no longer required. Another maid prepares to move belongings from the house, sees the shoes, and puts them on. As soon as she does, she picks up the gun and walks back into Kyle's house and a single gunshot is heard.

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