The history: In a series of flashbacks, we see Finch teaching the computer program that we know so well, aka the Machine, much as a parent would a genius child. The modus operandi, which we saw touches of last season, is now fully spelled out. The Machine uses any available lens to see what's happening in the world, and a variety of phones - landlines in phone booths, cell phones, smart phones (and sometimes a flash on an available screen) - to "talk" to Finch and later Reese. The key point in the teaching of the Machine is Finch's insistence that it not operate as Finch's guardian, but as a guardian of the greater good for all humanity. This utilitarian principle - the good of the many outweighs the good of the few (in this case, of the one, Finch) - is pivotal in the central arc which Person of Interest is now in the heat of following.
The central arc: Finch has been kidnapped by Caroline Turing aka Root - the finale of the 1st season's person of interest - and she's even more formidable that we might have realized last season. In fact, she may as much a mastermind as Finch, except she uses her talent for evil. Reese will have his hands full tracking her down, which he'll need to do to find and liberate Finch. "Liberate" is what Root says she wants to do to the living Machine - by which, I assume she means, liberate it from Finch's control, to the degree that Finch does exercise control. Reese, in any case, scores a good scene and move with the Machine, when he tells it that he has no intention continuing to save persons of interest in need, unless and until the Machine helps him rescue Finch. It's a great Asimovian laws of robotics moment, in which Reese is asking the Machine to override its most fundamental programming, instilled by Finch, on behalf of saving Finch. And the Machine agrees.
The standalone story: Ken Leung, of Lost fame, plays the victim, on the verge of being murdered by white supremacists. Reese has his customary great moves, and in the process of saving the victim picks up a dog - savage to enemies, docile to Reese - which will make a good addition to the cast. Carter and Fusco are also on hand, with Carter once again saving Reese, and Fusco noticing that Reese is not invulnerable - a recognition which will likely have greater significance later this season.
So Person of Interest is off to fine, taut start, with a nemesis in Caroline, a provocative continuing story with Finch still under her control, and some much needed information about how the Machine came to be what it is now is.
See also Person of Interest of Interest ... Person of Interest 1.2: Reese and Finch ... Person of Interest 1.5: Potentials ... Person of Interest 1.7: Meets Flashpoint and The Usual Suspects ... Person of Interest 1.8: Widmore and Ben, At It Again ... Person of Interest 1.9: Evolution of a Series ... Person of Interest: 1.10: Carter Returns the Favor ... Person of Interest 1.11-1.12: Realignment and Revelation ... Person of Interest 1.14: Reese as Ronin ... Person of Interest 1.16: Meets Wall Street ... Person of Interest 1.17: Hearts and Places ... Person of Interest 1.17: Double Ecstasy
"As a genre-bending blend of police procedural and science fiction, The Silk Code delivers on its promises." -- Gerald Jonas, The New York Times Book Review
"Daddy, this is the best book I ever read!" - Molly Vozick-Levinson, age 12 at the time