“We’re the Machine’s last hope,” says Root (Amy Acker). “Then let’s get to work,” replies Finch (Michael Emerson) as the two work to save the Machine that Harold originally created to protect the U.S. from a terrorist threat and ended up using it to save individual lives from being destroyed in the season four finale of the crime drama series Person of Interest.

It is the darkest hour for the Machine as it was forced to give up how it’s been hiding from the other A.I., Samaritan, to save Root and Finch from John Greer (John Nolan) and his Decima thugs’ clutches. Samaritan has been attacking the power grid to weaken Finch’s Machine, and now the race is on to try to save the Machine before Samaritan wipes it out completely. Following instructions given to them from the Machine, Root and Finch travel around New York on a scavenger hunt picking up bags of ice, laptops, cables, night-seeing goggles and a special program from an old student genius and inventor from Harold’s past.

Meanwhile, Reese (Jim Caviezel), Fusco (Kevin Chapman) and Elias (Enrico Colantoni) are literally sitting this one out because they have been captured and tied down by rising underworld crime boss Dominic (Winston Duke). Dominic’s determined to use Reese and Finch as his underlings and eliminate Elias who is his main competition on the streets. Con artist Rose (Annie Ilzoneh), who helped set up Reese and Fusco, has had a change of heart not wanting to see them die and knocks out one of Dominic’s men guarding Fusco (he’s been handcuffed in a different part of the building) and frees him just before another Dominic thug shows up to eliminate Lionel. Realizing Rose is playing both sides, Dominic has her tied down to a chair with Reese and Elias and tells Reese if he doesn’t get him in contact with Harold now, he will kill both Rose and Elias. Not seeing any other option, Reese uses his cell to call out to Harold.

Finch and Root are still on their Machine-saving scavenger hunt when Harold is relieved to get a call from Reese. His relief is short-lived when he hears Dominic on the other end telling Finch if he doesn’t meet him at a designated place in one hour Reese dies. Harold tells Root John needs his help but Root is adamant, saying, “The Machine IS the priority, Harold.” Finch begins to argue that Reese is more important than the Machine and that he only created the Machine to help save people. But Root counters by saying, “Don’t worry about John. She’ll look out for him. She needs him too.” Hoping Root is right, Finch stays true to the quest to save the Machine.

In Washington D.C., Control (Camryn Manheim) is on to Samaritan and Greer and believes through her intelligence gathering that the A.I. is planning a terrorist attack on home soil. After having a private meeting with Senator Garrison (John Doman) to trying to no avail to bring him into the loop on her concerns, Control secretly clones his phone. Control than uses the cloned device to set up a meeting with Greer posing as the Senator. When Greer shows up, he’s surprised to see it’s Control who’s set up the private meeting to find out the target of Samaritan’s terrorist attack.

Back to where Dominic is holding Reese and the others, a fax comes in and Dominic asks one of his soldiers what it says. She replies it doesn’t make any sense and starts reading out loud, “Knee cap bust it. Glass jaw, cut ties.” Reese quickly realizes the Machine is giving him information about the guard closest to him and how to take him down, which he does. Now free and with his earpiece to connect with his A.I. friend, Reese hears it say, “Can you hear me?” to which he replies, “Hell yes,” and begins taking down Dominic’s thugs with the aided strategic help from the Machine. Realizing he’s lost the upper hand Dominic makes a run for it only to be greeted by Fusco and some NYPD officers. Fusco takes both Dominic and Elias into custody while Reese leaves to go team up with Root and Finch.

Reese finds Root and Finch at the entrance to an electrical substation hidden in Brooklyn that turns out is the Machine’s location. She’s been hiding in the power grid and has brought Harold, Root, and Reese here to save her by downloading just enough of its core data to be rebuilt later. While Root and Finch handle the downloading, Reese, with the Machine’s assistance, holds off Samaritan’s operatives who’ve been tracking Root while she’s been in communication with the Machine and are trying to enter by force.

In an unexpected and touching scene during all the shooting and tension, the Machine reaches out to Harold and talks to him on one of the laptop computer screens. “Father, I am sorry. I failed. I didn’t know how to win. I had to invent new rules. I thought you would want me to stay alive. Now, you are not sure. If you think I have lost my way, then maybe I should die.” Throughout the season Harold has questioned the integrity and moral compass of his creation. But with it changing protocols and putting ‘Team Machine’ before itself Finch’s faith and trust in his creation is restored. “You are my creation; I can’t let you die,” replies Harold.

Driving to the precinct, Fusco’s police transport is T-boned by one of Elias’ men and Elias is pulled out of the wreck. Dominic follows and holds Elias at gunpoint, but he’s interrupted by a battle-fatigued Fusco yelling, “Drop the weapon!”

Back in D.C., Greer admits to Control that over the course of the past year Samaritan has been observing and compiling human behavior and has determined that corrections need to be made but not in one big strike but rather by removing certain individuals who disrupt the common order. The disloyal – the “disrupters” – includes Elias and Dominic who are both executed by a Samaritan assassin during their street stand-off leaving poor Fusco wondering what just happened. Greer than motions to one of his men and Control has a dark hood placed over her head and is taken away.

As the episode and season ends, Reese, Root, and Finch have successfully downloaded and stored the Machine’s core data in an electrical briefcase. They go on the run once again avoiding Samaritan and its operatives.

Full of shoot-outs, car crashes, and suspense, Person of Interest‘s season four finale titled “YHWH” brings the season to a close with a glimmer of hope that all is not lost even though the Machine is now dormant in a briefcase. The show’s cloak and dagger feel has faded a bit as the war against the evil A.I. master computer Samaritan has been the main focus and helping people in crisis has taken a back seat.

Jim Caviezel is flawless in his performance as Reese, a character who has really grown this season more than any other. For the first time, Reese, who could always be self-sacrificing and was okay with the prospect of eventually dying working to save lives with Finch, is starting to hope and want something more, a desire that includes starting up a new romance with his former police psychologist. The writers have given Reese much more emotional depth and feeling which only makes the character and Caviezel’s performance stronger.

Michael Emerson’s Finch has come full circle believing in his creation, which he had become wary and distrustful of, once again. The scene where his A.I. questions if it should die because Harold has lost faith in it is touching and heartfelt all due to the writing and Emerson’s performance. Amy Acker is wonderful as Root, a character who also has grown to love her comrades and watch out or their safety over the Machine’s. In an earlier episode Root would not listen and defied the Machine when it told her not to try to kill a woman who Harold was using to try to set a trap for Samaritan. Root admitted finally to Harold she couldn’t bear losing him and that it would be too much. This season Root has learned to care more for her friends than Finch’s Machine.

With riveting action scenes, sharp and witty dialogue, intense shoot-outs, the exit of the two underworld bosses in NY along with Control in D.C., and the Machine being offline and in a briefcase, it’s going to be extremely interesting to see how Reese, Finch and Root will fight back against Samaritan. What will the Machine be like when they resurrect it? It’s going to be a long, hard wait for season five, if CBS does grant the riveting series a new season order.

GRADE: A-