The series revolves around a computer program for the federal government known as "The Machine" that is capable of collating all sources of information to predict terrorist acts and to identify people planning them.
A team, consisting of John Reese, Harold Finch and Sameen Shaw follow "irrelevant" crimes: lesser level of priority for the government.
According to Nielsen Media Research, the episode was seen by an estimated 8.94 million household viewers and gained a 1.3/4 ratings share among adults aged 18–49.
The episode received highly positive reviews, with critics praising Amy Acker's performance, the writing, ending, and the talk between the Machine and Samaritan.
He interrogates Luski, who confesses that he works for MI6 and that his employer was Greer's Deputy Chief Blackwood (Michael Siberry), a KGB member.
Finch (Michael Emerson) and Root (Amy Acker) convince Shaw (Sarah Shahi) to stay in the train station until Samaritan stops pursuing her.
When the Machine refuses to talk, Samaritan continues expanding its detection of threats, causing Fusco (Kevin Chapman) and the rest of the precinct to exhaustively pursue criminals.
In its original American broadcast, "The Cold War" was seen by an estimated 8.94 million household viewers and gained a 1.3/4 ratings share among adults aged 18–49, according to Nielsen Media Research.
Matt Fowler of IGN gave the episode a "great" 8.6 out of 10 rating and wrote in his verdict, "'The Cold War' set up the pieces for what looks to be a catastrophic middle chapter of this trilogy.
Samaritan appeared to be crashing the stock market in an attempt to finally reveal itself to the world as something to heed-slash-worship, and Shaw's decision to help could spell out doom for everyone involved.