We've seen Don Draper do some pretty despicable things before – commit adultery, steal a dead man's identity, etc. But he never struck us as the murderous type. After a chance encounter with a former flame, Andrea Rhodes, an under-the-weather Don endures a fitful night of delirium. He has sweaty, passionate sex with Andrea, only to kill her as punishment for luring him to cheat on his new wife, Megan. It may not have happened in reality, but it was still plenty upsetting to watch Don strangle a helpless woman to death, even if she was just serving as a metaphor for his previously unfaithful nature.