Last night's edge-of-the-seat episode of “Person of Interest” titled "Dead Reckoning" was the culmination of the previous episode, which ended with a car wreck. After the wreck, Agent Donnelly was shot in the head by Kara Stanton. Detective Carter awakened after Kara took John, whom she injected into his neck with a hypodermic needle. Finch continued to call until Carter answered the phone. She told him that John was taken, and she was handcuffed. He told her to focus and find the keys and then get away from there. She told him that it was his old partner from the CIA who was thought to be dead.
The scene opens on a bus with Kara and Agent Mark Snow the three who worked together in the CIA.
Fusco called Carter to tell her that Agent Donnelly was dead. They are looking for Carter, who they knew were working on a case together. As Carter bends down at the wreckage looking for something, Fusco holds up a gold ring that she was looking for. When he asks her what is going on, they meet with Finch who tells them about Kara. Finch has her death certificate and some other papers. Carter told them that Agent Snow was with Stanton, and that he told her she was planning something big. Carter mentioned something about a hard drive, and Snow was wired with a bomb vest.
Meanwhile, Finch and Snow are sent to pick something up behind closed doors. When they open, a person with a Russian accent tells them that their boss must have very deep pockets, and the drive was formatted to her specifications; however, the price has gone up by $50,000. Kara is listening through John's earpiece, the same way he and Finch communicated. She tells him to break the guy's neck, but he hesitates. She is across the street and shoots him and his accomplice as both John's and Snow's vests light up. Then she tells them to take the drive and leave, and it is his last warning.
Flashbacks show Agent Snow separately giving both John and Kara orders to eliminate each other upon completion of a Far East mission. He tells her that they clean up their own messes. Then she shoots him upon completion of the mission, but his vest protects him. She awakens in a hospital with a wrinkle-faced man standing over her holding a computer.
The three are in a diner, Kara tells John to eat, as he needs his strength, eventually he will give in. She sends them out to follow two men who are ATF agents. As Mark nearly kills one of them, John stops him. He tells Snow that he will play along with Kara's game, but killing civilians is not part of it. Snow agrees. They open the trunk and grab the ringing phone, but before ditching the phone, John sends a text to Finch.
Carter calls Finch after checking out the hard drive, it is made exclusively for government and military installations. Just then, Finch receives a text with a military code for unexploded ordnance, cluing Finch in that he is wearing a vest. They check the origination of the call, and it is in a dumpster.
Dressed as ATF agents, John and Mark are called to a bomb threat. The building is home to a Department of Defense clandestine operation. Knowing that the Delta Force will be shooting at whoever comes from the elevator, they are prepared. Kara raises the stakes and gives them 15 minutes before their vests explode.
Finch tells Carter and Fusco that the drive could shut down entire countries. As Reese tries to reason with Snow, he is unshakable. Reese calls Finch who tells him that she is attempting to steal a cyber weapon with code name Cygnus. This could shut down their machine. Snow refuses to let John erase the hard drive, and they start fighting. Kara shows up just as John completed the erasing. She puts the drive back in as John tries to reason with her. She gives them another five minutes on their vests and puts them in the elevator and closes the door, remaining outside.
As they are leaving, Snow knocks John down, and he gets into the elevator. Carter and Fusco show up to help John out of the vest. He sends them away because he cares about them. Reluctantly, they leave.
John meets with Finch who attempts to shut the timer on the vest. John gives him the hard drive and tells him to check it out. With less than two minutes for the timer to go off, Finch puts in the correct code. Whew!
Kara speaks to the old man who gives her the name of the person who; he believes does not exist on any known database. She writes it down on a pad and proceeds to her car. In the back seat is Snow, with vest ready to blow. He tells her that she was right about him, that being dead, he is gonna be great at it. Just then the car blows up in a fiery explosion. On the sidewalk is a piece of paper with the name she wrote down; Harold Finch.
Agent Ross comes to visit Carter to tell her that they identified the suicide bombers who broke into the DOD facility; Kara and Snow. Snow fits the description of the "man in the suit," officially closing the case and having his identity known.
Finch gets as much information as he can from the drive and finds out that it will be going live in five months. But until then, on to the next "Person of Interest."