On this week's Person of Interest...
Reese continues to mourn the loss of Carter, but Fusco has followed to watch over him.
Shaw helps Finch watch over the person of who interest who worked with the NSA and also built Samaritan, a system similar to Finch’s the Machine.
Flashbacks revealed that Finch wanted to build a system to help his father cope with his diminishing memory.
Vigilance tried to get to the man, but the government captures Finch, Shaw and him. Control reveals herself demanding the whereabouts of the Machine or she will kill them.