On this episode of Person of Interest...
Reese tricks Finch into helping with a new number, a computer whiz named Claire following a dangerous game around the city.
With numerous codes involved, Reese, Finch and even Fusco attempt to crack them to try and protect Claire, who happens to be hunted by a black ops group.
The game is created by Samaritan, looking to recruit assets and take down its computerized competition (such as the one the black ops group was creating).
Finch tries to plead with Claire not to finish the game, but she does so anyway. She becomes Samaritan's asset.
Finch reveals to Reese and Shaw the underground abandoned subway spot that has become the new headquaters for the POI team.
Finch is back and ready to work again.