Reese is dealing with the death of Carter in this Person of Interest scene. He isn't happy about it.
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Finch worries a member of the team will take the search for justice too far on Person of Interest. "The Devil's Share" is the tenth episode the show's third season.
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Person of Interest Season 3 Episode 10 Quotes

We're out of options. We need Root.

Shaw

Does survivor's guilt pass when everything that has happened actually is, in fact, your fault?

Finch