There's a veil of sadness, a shroud of bittersweet happiness, and a toupee of hope over the series finale of Person of Interest, which ended its five-season run in spectacularly emotional fashion with "return 0." But given that Person of Interest always lived in that realm that was so close to our own reality and never pulled away from the potential terror of nationwide surveillance and disrupted privacy, that mixture of emotions — both good and bad — felt perfect as a way for this prescient series to sign off forever. But my goodness! This episode was heavier than Fusco (Kevin Chapman) after a mid-day cheeseburger and fries, and perhaps the most difficult episode of the series to watch.

After Harold Finch (Michael Emerson) unleashed the Ice-9 virus that would take out Samaritan and everything else with an internet connection — including our beloved Machine — in the last episode, all that was left was mopping up a backup copy of Samaritan that we learned existed in the basement of the Federal Reserve building New York City. The information came out in classic Person of Interest style: through broken timelines, from various perspectives, and with a dab of uncertainty. But one thing that was for certain was that death was in the air as we saw Finch having a rooftop conversation with the Machine (Amy Acker, representing the hallucinatory embodiment of the Machine) and heard the Machine's chilling voiceover from the season premiere reminding us that "I don't know if anyone made it." This was a series finale, after all, and Person of Interest was never going to let everyone make it out alive.

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An early montage of clips made everyone a candidate to meet their maker. Finch had a bullet hole in his gut. We saw a glimpse of Reese with a gun at his head. Fusco was bleeding from the side. And the Machine was slowly failing. Death was everywhere in "return 0," we just never knew when it would strike, which made the whole hour a test of fans' tickers. Those looking for a truly happy ending would not leave satisfied, but again, Person of Interest was too busy using shades of reality to paint a fairy-tale sendoff traditional to most TV series. I don't know about you, but my teeth are ground down to stumps from all the tension.

Ultimately, the plan to stop Samaritan was anything but simple: Samaritan was uploading its final copy onto a Russian satellite to ride out the Ice-9 virus in the Earth's orbit until it was safe to beam back down, and Harold was going to upload his final copy of the Machine to the satellite for one final battle for A.I. supremacy. It came with a hitch though, as the only dish capable of uploading to a satellite was identified by Samaritan, which took control of an off-shore Destroyer and launched a cruise missile at the dish. In other words, whoever was sent to upload the Machine was going to get a face full of missile as well.

Michael Emerson, Jim Caviezel; <em>Person of Interest</em>Michael Emerson, Jim Caviezel; Person of Interest

Finch locked Reese in the Federal Reserve vault to go on the suicide mission himself, but we later found out that Reese and the Machine had a deal: Reese would go on the suicide mission to save Finch's life in order to "pay him back all at once" for all the things Finch did for him. *sniff* This coming right after Finch admitted to Reese that he always knew Reese would be a good employee but he was astonished about how great a friend he became. *audibly sobbing* And later Reese would fulfill his mission and upload the Machine while Samaritan agents closed in and shot him up, with the missile clearing the whole rooftop in a fiery blast seconds later. *uncontrollable weeping* John Reese died so that his best friend would live. John Reese died because without Harold Finch, he would already be dead. John Reese died because Finch gave him the one thing he always needed: purpose. John Reese died because he loved Finch like a brother. John Reese died a perfect hero's death. This was always John Reese's path. Goodbye, you wise-cracking, knee-shooting, mumbling stud.

You may be crushed under the weight of sadness, and you're absolutely forgiven if that's the case. But the greatest strength of "return 0" was its practical message about death. The Machine — through Root's voice and body — waxed philosophically with Finch about the meaning of death and how it should be processed, her all-seeing eye having witnessed 56 million people die in the last year alone. As she strove to understand people, she needed to understand death. "Everyone dies alone," she repeated, missing the memory of the second half of the phrase that would drive the finale. And as death lingered in the air and the second part of the lesson remained elusive, "return 0" dropped an anvil on its audience in Reese's death, the severity of the situation making every scene more brutal to watch.

But in the end, the Machine did recover that last part of the phrase, by recalling two cops having a conversation. (I loved the way the show made sure we knew the Machine learned its lessons from regular people in addition to the characters we knew.) The young jaded cop said, "Everyone dies alone." His veteran partner added, "Sure, everyone dies alone. But if you mean something to someone, if you help someone, or love someone, if even a single person remembers you, then maybe you never really die at all."

Michael Emerson, Kevin Chapman, Jim Caviezel; <em>Person of Interest</em>Michael Emerson, Kevin Chapman, Jim Caviezel; Person of Interest

They're manufactured consolable words that might appear on a "Sorry for your loss" Hallmark card, but in this case, they rung strong. The question lingering on Finch's mind was whether it was all worth it. Did their job — sorting through and saving irrelevant numbers — mean anything? Did Reese die for something? The answer was yes. The Machine helped people, Finch helped people, Reese helped people. Team Machine mattered to each other and they mattered to the world.

It's a powerful statement that, like most of the philosophy in this show, bled over to our lives. You may not be able to create an artificial intelligence that can help save lives. But the message was that your life isn't to be wasted. That you can do good in your life. And that if you even mean something to one other person, you've left a positive effect in your time on Earth.

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In the end, the Machine defeated Samaritan and lived on. Shaw survived and took Bear. Fusco got his cheeseburger, a questionable new chapter of his life in front of him. And Finch got the opportunity for the most elusive gift: a chance at a normal life as he reunited with Grace (Carrie Preston). And Person of Interest didn't ride off into the sunset with happy endings for all. Instead, it stayed right where it always has been, relishing real life and the good and bad that come with it, but never giving up hope for something better.

Team Machine, from Finch to Reese to Carter to Root to Shaw to Fusco, all left a lasting, positive impression on each other. And the series left a lasting impact on us. To the writers, producers, actors, and crew of Person of Interest, to Greg and Jonah, thank you for five wonderful seasons. Person of Interest may be gone, but it will never be alone because it will always be remembered.

NOTES OF INTEREST

- Fusco, after Reese put the police chief in a sleeper hold: "Great, I can kiss my pension goodbye!"

- There were a lot of statements made in the series finale, one of the big ones being that it's hard to find a good cop. Was the whole department under the bankroll of Samaritan?

- I really liked the explanation of Harold's bird aliases as a tribute to his father.

- The story of Jeffrey, the sniper who shot Root, was fascinating. Jeffrey never signed up to be part of Samaritan's army, and — though Root's fans may disagree — he was never a true villain. He didn't even really know who he was working for. Yet he wasn't let off the hook for what he did even though he was a manipulated cog in Samaritan's plans. Shaw shot him for revenge because that's what she needed. But his death wasn't joyous; it was a reminder of how complicated and unfair life can be. This was a statement on the difficulties facing ex-cons as they try to rehabilitate themselves into the real world.

- Finch, waiting for the Machine to finish a story: "The suspense is killing me... in addition to the gunshot wound."

- The Machine to Shaw, on behalf of Root: "If you were a shape, you were a straight line. An arrow."

- Reese's goodbye to Fusco: "Try not to die." Fusco: "Yeah, I love you too."

- Reese, after smashing a gold bar over a bad guy's head: "Midas touch." CLASSIC REESE! I miss you, man.

- I'm so glad that Finch and Reese got to spend so much time together in this last episode, and had a couple heart-to-hearts. Person of Interest has expanded way beyond its initial premise of a suave ex-military man doing the muscle work for a geeky billionaire, but the core of the show has always been about the relationship between Reese and Finch.

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