The vulgar, egotistic junkman Harry Brock has come to a swanky hotel in Washington to make crooked deals with government big-wigs. He has brought with him the charming but dumb ex-chorus girl Billie, whose lack of social graces embarrasses even Harry. Billie must be taught some of the amenities, and a few basic bits of information. The young, idealistic magazine reporter Paul Verrall, who has been investigating political skullduggery and is interested in Brock's activities, agrees, for a salary, to educate Billie. He finds Billie has a natural honesty and a frank streak in her, and she begins to learn about history, politics, and what Harry really is and what he wants.
At a dramatic moment she rebels against being merely a tool in Harry's crooked schemes. This precipitates a crisis, as Billie readies to leave Harry for a new life of her own. At the end, Paul and his promising pupil turn their backs on Brock and strike out on their own.
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