Just Write (1998)

Synopsis
This comedy blends a romance centered upon mistaken identity with a satiric, insider's look at the film industry. Harold (played by Jeremy Piven) lives in Hollywood and earns his living driving a tour bus that makes the rounds of the homes of the stars. One day, Harold sees his favorite actress, Amanda Clark (Sherilyn Fenn), in a restaurant and impulsively introduces himself. Amanda, who was discussing screenwriters with her agent only moments before, is for some reason convinced Harold is a writer -- and Harold is too pleased to be talking with Amanda to correct her, especially when she suggests they meet to discuss an upcoming project. However, when Harold is assigned to rewrite a script Amanda is considering, Harold has to find a way to make his illusion a reality. ~ Mark Deming, All Movie Guide