The screenplay for Pretty Woman was originally entitled $3,000 and was much darker and more dramatic. Remember that cutesy scene in the film where Edward thinks that Vivian is concealing drugs in the penthouse bathroom, but it turns out she's only holding dental floss? In the script it goes a little different:
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In the finished film, Vivian claims that she doesn't use drugs, but let's examine the evidence, shall we? There are numerous points throughout the movie where Vivian appears to be unusually energetic, restless, and talkative. In fact, her loopy behavior becomes the source of a constant running gag: There are no less than five occasions in the movie where Edward tells Vivian to stop fidgeting. And, of course, fidgeting, restlessness, and manic energy are all common signs of cocaine use.