Continuity mistake: When Frank pursues the killer at the lake house, through the snow-clad forest, his breath doesn't show. But he comes from a warm house directly out into a freezing night air.
Continuity mistake: In the scene where she takes him into the boutique, she goes into a dressing room with a curtain across the opening. The shot pans from looking over the curtain, where it has 5 ruffles, to Kevin Costner and then back over the curtain which now only has 3 ruffles even though she hasn't come out. (00:27:45)
Answer: She admits that while high on drugs she had a fit of jealousy and hired an assassin to kill her sister.
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