Question: who plays helen of troy fall of a city
[{'answer': 'Bella Dayne', 'provenance': [{'wikipedia_id': '53358988', 'title': 'Troy: Fall of a City', 'start_paragraph_id': 7, 'start_character': 12, 'end_paragraph_id': 7, 'end_character': 23, 'bleu_score': 1.0, 'section': 'Section::::Cast.\n'}]}]