It's their first meeting. Carter sits next to Reese in this scene from Person of Interest.
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Person of Interest Season 1 Episode 12 Quotes

Whatever he was working on, he sold it to the government for a dollar. So that means it was either something worthless or priceless.

Will

Finch: I hope you understand that there are certain things I can't tell you.
Reese: Oh, I understand completely, Finch.