Question: when does emily come back in criminal minds
[{'answer': 'season 12', 'provenance': [{'wikipedia_id': '24977933', 'title': 'Emily Prentiss', 'start_paragraph_id': 2, 'start_character': 39, 'end_paragraph_id': 2, 'end_character': 48, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]