Holmes runs into a woman from his past during an investigation on Elementary. "Poison Pen" is the fourth episode of the show's second season.
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Elementary Season 2 Episode 4 Quotes

It doesn't matter when I made the assumption, all that matters is that I was right.

Sherlock

[after whip crack] Cause when you're night ends with a dead man and a chem suit, why not start your morning with a live unfolding of a bull whip.

Joan