Lost is probably the weirdest popular television show of the 21st century — so far. What started out as a simple tale about a bunch of people stranded on an island soon became a mixture of science, magic, polar bears, time travel, smoke monsters, and mysterious fish biscuits. Lost 's rabid fanbase still idolizes these disparate concepts, and how they somehow came together to tell a six-season story. The show was the definition of high-concept television and yet it used these elements in conjunction with emotional, moving character stories, which prevented the series from being bogged down by the frequent talk of spiritual mysticism or electromagnetism. In fact, it uses one of its loftier science-fiction elements for it's only Christmas episode, and boy is it a doozy. If you're looking for an episode of television to truly remind you what the holidays are about, then dedicate some time to watching Lost's Christmas episode, "The Constant."
Technically, "The Constant" is more Christmas-adjacent than it is strictly a themed episode. Unfortunately, we don't get a sequence where Jack, Sawyer, Kate, and the rest of the gang put their differences aside to sit around a big campfire beneath Christmas lights fashioned out of scrap materials and sing "We Wish You A Merry Christmas" while the smoke monster leaves presents in everyone's tents. Instead, we get a time-travel story about long-time Island dweller Desmond, whose consciousness becomes unstuck in time.
In 2004, Desmond is a man who has been on a tropical island for over three years on his way to a nearby freighter that may provide a means of escape. In 1996, he's an enlisted solider in boot camp. Due to the overall weirdness of the Island, as well as a bunch of sciencey stuff that isn't super important, Desmond's consciousness starts transferring between 2004 and 1996. Suddenly, Desmond has lost any memory of what happened to him between those years, and he finds himself on a mysterious boat with no recollection of how he got there.
After a few back and forths through time and a conversation with resident physicist Daniel Faraday, Desmond is told that as he goes back and forth through time, he runs the risk of suffering a brain aneurysm — his physical brain won't be able to keep up with the shifts in time. Faraday tells Desmond that he needs a "constant." Something that exists in both 1996 and 2004 that he has a strong connection with. He decides the best person to communicate with is the woman in the picture that Desmond is holding in 2004, the love of his life, Penelope Widmore.
Now, this is where Christmas begins to come into play. Desmond and company form a plan to get him in touch with Penelope in 2004 so that his strong connection can "anchor" him — because of course True Love can save lives that way. But in 1996, Penny is none too happy with Desmond. He goes through many hoops that year to try and track down Penny, who has changed her number and made every attempt to avoid him. Desmond eventually tracks her down and gets her phone number, and asks a simple favor. Desmond, in the year 1996, asks Penny to pick up the phone when he calls on Christmas Eve 2004. It's an absurd request to make, and when Desmond calls it's clear he's unsure whether he will hear Penny's voice on the other side.
But he does.
On Christmas Eve 2004, Penny gets a call from the man she's been searching for since he went missing three years prior. While the circumstance is truly a Christmas miracle, the episode doesn't directly acknowledge the Christmasness of it all until the final few minutes. However, thematically it's hard to make a more Christmas-appropriate episode of television.
Christmas, more than being about presents or chestnuts or ornately decorated trees, is about spending time with the people that are most important to you. From Jan. 1 to Dec. 24, a whole new year of experiences — good and bad — have occurred and defined how the year prior will live in your memory. Christmas is the beginning of a week-long cool-down process (ending with New Year's Day) as you enter into the new year, and it's a time to ground yourself and spend time with the "constants" in your life. Desmond is pushed by the fear of death to reach out to his constant, traversing space and time just to organize a phone call. But the moment of relief that washes over his face when he first hears her voice is exactly the reason that Christmas, as a holiday, is dedicated to bringing people together.
The holiday helps everyone keep from being lost in their own way, which is exactly why "The Constant" should be on your must-watch list of Christmas episodes. Just remember to have tissues handy.