But one night last month, as Diaz stepped off the No. 6 train and onto a nearly empty platform, his evening took an unexpected turn.
He was walking toward the stairs when a teenage boy approached and pulled out a knife.
"He wants my money, so I just gave him my wallet and told him, 'Here you go,'" Diaz says.
As the teen began to walk away, Diaz told him, "Hey, wait a minute. You forgot something. If you're going to be robbing people for the rest of the night, you might as well take my coat to keep you warm."
The would-be robber looked at his would-be victim, "like what's going on here?" Diaz says. "He asked me, 'Why are you doing this?'"
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