Continuity mistake: Right after Frank gets shot he shoots Portman and you see someone helping Frank get his jacket off as he's lying on the ground. The camera angle changes and you see his jacket back on and someone is starting to help him take it off again.
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.
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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