Question: who is the killer in the movie zodiac 2007
[{'answer': 'Zodiac', 'provenance': [{'wikipedia_id': '2654186', 'title': 'Zodiac (film)', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 6, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]