In fictionland, dealing with Christmas lights is extremely difficult. No matter how neatly a character puts them back into the box, they will be horribly tangled the next time they're taken out of it. There will probably be one broken bulb that makes all of them go out (something that can genuinely happen depending on how the lights are wired, though nowadays most lights companies know better than to sell strings of lights wired in series specifically because of this trope) — woe betide the characters if they forget to check for that before hanging up the string of lights. They may also hang up the lights, only to find out that the cord is just a little bit too short. And when they finally plug it in, the whole thing will probably short out.
Even if the characters do manage to rig up the lights and they work, Finagle's Law dictates that something will go wrong later. Maybe someone will accidentally ruin the display, or the characters have to take it down and redo everything because someone isn't happy with how it turned out.
Christmas lights even carry a risk of Amusing Injuries. Accidents involving the string of light — or the mere act of turning it on — may lead to a Harmless Electrocution. If someone has to climb a ladder to hang up or try to fix the lights, expect them to fall at least once. Sometimes, a character will inexplicably end up tangled up in Christmas lights.
Over-the-Top Christmas Decorations is a common cause of Christmas Light Chaos, but those who prefer more modest decorations are not immune.
- The Too Incompetent to Operate a Blanket sections of this Star Shower Motion Laser Light ad feature a guy having trouble with a traditional string of lights: First he has to untangle them, and then he spends hours hanging them, only to find out that they don't even work when he tries to plug them in.
- Nipper & Gramophone's Christmas Tales: Downplayed example in "The Wire". While setting up the lights doesn't seem to have been a problem for Gramophone, the cord is still too short for him to reach Nipper and he ends up yanking it out (don't ask where it was plugged into) when trying to get closer, causing the lights to flicker out.
- Doorman of the Great Lakes Avengers lost his estranged dad when the latter slipped and fell off his roof while hanging up Christmas lights. Happily for him, Doorman is a Psychopomp who just happened to get assigned to collect his dad's soul, so he got an opportunity to say goodbye and clear the air between them.
- In one of The Simpsons comics, Homer is having trouble untangling the Christmas lights because Snowball II is playing with them.
- From a The Buckets strip: In January, Larry neatly puts the Christmas lights back into the box. The next December, they're horribly tangled.
- Garfield has used this many times:
- In the 1991-12-22 Sunday strip, Jon opens the box of Christmas lights and finds a tangled mess. He decides "screw it", and hangs them up without bothering to untangle them.
- The 1992-12-18 strip is about the classic "find the one bad bulb that makes them all go out" problem. In the 1996-12-17 strip, Jon faces the same problem and manages to solve it, but electrocutes himself in the process. Similarly, the 2017-12-10 Sunday strip has Garfield being haunted by the ghosts of Christmas past, present and future... and the dead bulb on their Christmas tree, which scares the three ghosts.
- The 1992-12-20 Sunday strip is about Jon rigging up a lot of lights, only to find out that the cord is a little too short.
- In the 1995-12-17 Sunday strip, Jon somehow gets tangled up in the Christmas lights and ends up hanging upside-down from the roof. The same happens in the 2014-12-01 strip.
- In the 1997-14-12 Sunday strip, Jon gets electrocuted by the Christmas lights when Garfield flips the switch. The following strip shows him injured and covered in Christmas lights. Similarly, the 2009-12-08 strip shows Jon covered in pine needles and Christmas lights. And the tree was still crooked.
- In the 1998-12-11 strip, Jon somehow gets himself and the Christmas tree tangled up in Christmas lights. In the next strip, Jon's struggle with the decorations is unseen, but obvious from the sound effects. Two days later, Jon successfully rigs up the lights. Unfortunately, turning them on blows a fuse.
- In the 2000-12-21 strip, it's shown that Garfield has been covered in Christmas lights after climbing someone's Christmas tree.
- Mickey's Twice Upon a Christmas: Played for Drama in "Mickey's Dog-Gone Christmas". Mickey's over-the-top Christmas lights actually work painlessly at first. Pluto then tries to put the star on the tree but falls, which causes some kind of fluid to spill onto an electrical outlet and short circuit everything. Mickey then scolds Pluto and sends him to the dog house. This makes Pluto feel unappreciated and disgraced, so he decides to run away from home.
- National Lampoon's Christmas Vacation: Clark is out on the roof all day and night trying to put up the lights on his own, only for none of his decorations to work, humiliating him in front of the family. Then Ellen realizes that the switch in the garage turns it on... after it gets turned on and off multiple times, making her husband angry enough to start kicking and destroying the lawn decorations.
- Henry Danger: In "Holiday Punch", Ray wants to decorate their Christmas tree with his grandfather's lights, which set on fire in their storage box. At the end of the episode, Ray's attempt to turn on the lights on the town's last remaining tree causes the tree to burn.
- DDE's "Det e ei lyspær et sted som itj virke" ("There Is a Light Bulb Somewhere That Doesn't Work") is about people looking for and not finding the one bad bulb that makes them all go out, as well as a few other Christmas-related annoyances.
- In "Twelve Pains of Christmas" by Bob Rivers, the second pain of Christmas is rigging up the lights. The angry man who tries to do that faces four problems: First the cord is too short, and they don't have extension cords. Then he can't figure out why the lights are blinking. Then all the lights go out because one of them did. Then, he needs a flashlight because he blew a fuse.
[in the last verse] FINE! YOU'RE SO SMART, YOU RIG UP THE LIGHTS!!!
- In Øystein Sunde's "Julekalenderen", the grandfather gets stuck in the Christmas lights and ends up dangling from them.
- Plonqmas: In “A Plonqmas Tale — 2009,” the snow leopard morph decorates his holiday tree by pulling ornaments from their tangled mess in a box.
- Invoked in the Futurama episode "The Farnsworth Parabox". Professor Farnsworth has produced a new invention contained in a cardboard box, but doesn't want Fry and/or Bender messing with it. Leela prepares a decoy box containing tangled-up Christmas lights and unlabeled liquor to keep them occupied.
- The Powerpuff Girls (1998): In "'Twas The Fight Before Christmas", the protagonists are preparing everything for Christmas with the Professor doing the tree. When it's time to light up the tree, the lights initially turn on then start turning off and on again. By the time the girls go to bed, the Professor is still trying to get them to work properly.
Professor Utonium: Every year it's the same darn thing! I can make three little kids out of seasoning, but I can't get these lights to work!
- In Rise of the Guardians, Santa's elves are decorating and one gets tangled in the Christmas lights.
- The (proper) series premiere of The Simpsons ("Simpsons Roasting on an Open Fire") has a downplayed example. Homer momentarily struggles to untangle the lights, and he accidentally falls off the roof of the house right as he finishes their setup, all for an unimpressive display — only the red lights actually turn on, and they flicker weakly.