Everyone, at some point, has a special moment they want to celebrate, or a once-in-a-lifetime opportunity that they're looking forward to experiencing because chances are very slim that they'll ever get the moment back. The nature of the event may vary; perhaps it's a significant birthday or anniversary milestone, or their wedding day, or a one-time showing of a television feature, or a limited-time sale of a highly sought-after item, or the chance to get a famous person's autograph. Whatever it is, a character will be looking forward to the event with great anticipation that it will be a very special moment for them.
But then something happens, usually just when the person is about to get the long-awaited experience. A distraction comes up that pulls the character's attention away for just a moment or two. Or a power cut happens right when the awaited moment is about to be televised. Or, as in superhero works, a villain or disaster comes up at exactly the wrong time and the hero has to go deal with the situation. Whatever the issue is, by the time it's been dealt with, the long-awaited event or opportunity has already passed, irretrievably gone.
The character's response to this can run the gamut from resigned acceptance, to dismay, to an outright Heroic BSoD in some instances, and it'll often be worse depending on the emotional attachment that was placed in the missed opportunity. If it's the latest in a series of unfortunate or inconvenient happenings, it can be the trigger for the character's Rage Breaking Point.
The Butt-Monkey and the Chew Toy are usually on the receiving end of this kind of incident. It can be the result of Failure Is the Only Option, or it can be part of a Humiliation Conga or a Yank the Dog's Chain moment. Depending on the severity of the missed chance, it may be a Rant-Inducing Slight. Sometimes this may be the reason a character is The Resenter.
Compare All for Nothing, where a character's efforts that have been exercised to get a specific result turn out to be, well, all for nothing. Also compare Life's Work Ruined, where the missed event or achievement in question is one that the character has spent years actively preparing for. Sometimes, this trope may take place because of Finagle's Law. See also Moment Killer, where it's more likely to be played for comedy.
See also Forgotten Birthday and Forgotten Anniversary, where the respective events are ruined for the celebrants because they're the only ones who actually remembered what day that day was supposed to be, and A Birthday, Not a Break, where everything else doesn't get put on hold just because it's your special day. See Wedding Smashers for wedding receptions, and Prom Wrecker for prom nights.
Cases of Rape as Drama and Rape Is a Special Kind of Evil may qualify if the victim was a virgin and specifically wanted to save Their First Time for a special someone or even for marriage. On a lesser note, the Sacred First Kiss is a big deal for a lot of people (particularly in anime works or in works set in Japan) because of this, as you can only ever have one first-time kiss in your life and it can't ever be done over; having the first kiss be taken by someone it wasn't intended for can therefore be a source of much angst.
Note that this kind of event is usually due to some issue or element outside of the character's control, and is therefore not the result of something they did, nor is it something they brought upon themselves; for situations where that's the case, you may be looking for Laser-Guided Karma or Dick Dastardly Stops to Cheat. Also not to be confused with Uniqueness Decay, where an item that's extremely rare at the time of its introduction ceases to be special once more of its kind show up enough for it to be commonplace.
- This has always been a recurring problem for Ash/Satoshi in Pokémon, often just missing out on winning a Pokemon League Championship in each region due to something happening to screw him over at a critical point in the tournament (if it wasn't a case of the opponent simply being just that much better), to the extent that fans got used to it being a Running Gag per region. In the very first instance, during the Kanto League, he lost a crucial match because his Charizard chose the worst time to be disobedient to his commands; he underwent a Heroic BSoD for a brief time immediately afterward. Which is why fans got thrown for a loop when he finally won the Alola League.
- In the Yu-Gi-Oh! anime's Kaibacorp Grand Prix arc, this trope is why arc villain Zigfried von Schroeder hates Kaiba. He, a rival game developer, was planning to present a gaming system to Maximillion Pegasus that was similar to Kaiba's, but Kaiba beat him to it. If Zigfried had gotten there first, his company would be enjoying the runaway success and fame that Kaibacorp now has; for this reason he wants to destroy and humiliate Kaiba in his own Grand Prix.
- In the Fantastic Four series, this is how Doctor Doom chooses to see the accident that scarred his face when he and Reed Richards were at college together—basically, Reed sabotaged an experiment of Victor's that would have otherwise been a great success. Of course, he conveniently chooses to forget that the whole thing happened because Reed saw a mistake in Victor's calculations and adjusted it, only for the prideful Victor to rebuff him and change it back, leading to the face-scarring explosion.
- 27 Dresses gives a variation of this, in that the special moment's ruin comes long before the event itself can take place. After having been a bridesmaid at 27 different weddings, Jane has been planning to wear her late mother's wedding dress when she finally has her own wedding...only to discover that her sister Tess, whose wedding she's also planning, cut up the dress to make it more "modern." With the stress of planning the wedding, having to deal with Tess's Bridezilla tendencies, the fact that Tess is marrying Jane's boss and love interest George (and is telling him all sorts of lies to convince him they are soulmates), and having just found out that her other love interest Kevin has written an unflattering newspaper article about her perpetual bridesmaid duties, finding out about the dress proves to be more than Jane can take.
- This happens to Mr. Wilson in Dennis the Menace, just at the point where he's about to show the neighbors the blooming of a flower he's been tending for 40 years; after the flower blooms, it will die, and Mr. Wilson's been waiting a long time for the moment to come. However, Dennis comes along at exactly the wrong moment to shout out that Mr. Wilson's house has been broken into, causing everybody to look away just as the flower is blooming, and by the time anyone turns back to look, the blooming has already happened and the flower is dying. For Mr. Wilson, it's 40 years down the drain, and it results in him ripping into Dennis with a vicious "The Reason You Suck" Speech.
Mr. Wilson: You're a pest. A menace. A selfish, spoiled little boy, and I've no use for you. You took something from me that I can never get back, something that means more to me than you ever will.
- This happens in the "Eyes" segment of the pilot film for the Night Gallery show. In it, a blind woman receives the gift of sight by buying the eyes of a sighted person and having them implanted in her. Her sight will only last for eleven hours, but when the operation is completed, a power failure in the city leaves her in the dark and unable to see.
- Carrie: Prom night, and especially being chosen as the prom queen, was supposed to be the highlight for the titular character, and she certainly thought it was a Throw the Dog a Bone moment after all the bullying she'd had to endure at school and the abuse she had to endure from her religious-nut mother at home. Unfortunately for Carrie, it turned out the resident Alpha Bitch had rigged the ballots so Carrie would win the prom queen title, just so she would be set up to get a bucket of pig's blood dumped on her as an act of utter spite. Unfortunately for everyone else, that proved to be the final straw that would result in Carrie going on a rampage with her telekinetic powers.
- Ray Bradbury's short story "All Summer in a Day". Once every seven years, the unrelenting rains on the planet Venus stop and there are two hours of sunshine. Most of the nine-year-old schoolchildren in a classroom can't remember the last time it occurred because they were only two years old at the time. However, one of them came from Earth five years ago, so she spent her first four years living in sunlight. On the day the sun comes out, the envious other children force her into a closet so she will miss the two hours of sunshine.
- On Friends, Monica and Chandler's engagement night was supposed to be a big deal, but it was ruined by the others. Joey was acting stupid thinking he could play a role that was half his age, Phoebe kept trying to prove that she could play music at their wedding even though her music style doesn't really fit weddings, and Ross and Rachel tried starting things up again.
Monica: See, I've been waiting my whole life to be engaged, and unlike some people I'm only planning on doing this once. So, uh y'know, maybe this is selfish and I'm sorry about it, but I was kinda hoping tonight could just be about that.
- In The Animal Shelf, one episode has Timothy wanting to see a comet, but he sleeps through it. The Living Toys (Gumpa, Woeful, Little Mutt, Get-Up, and Stripey) try to trick him into thinking he hasn't, but he's not fooled.
- In the Camp Lazlo episode "Lights Out", Scoutmaster Lumpus wants to see a comet that's been named after him through a telescope, but he has trouble putting the Jelly Bean cabin to sleep and having the lights in their cabin turned off. In the end, while he's trying to explain to them the reason why he wanted all the lights in the camp to be turned off, the comet passes by and he misses it, though the Jelly Beans manage to see it. The comet only passes Earth once every 50,000 years, so that was Lumpus' only chance.
- The Loud House:
- Played straight in "Left in the Dark", where Lincoln wants to watch a special episode of his favorite TV show, but ends up missing it because the power cuts out.
- Subverted in "Mall of Duty". One of Lincoln's favorite TV stars is signing books at the mall, and he does get his book, but has to give it up to bargain with an old lady. However, his parents then give him a signed copy of the same book.
- Subverted again in "Any Given Sundae", where Lily is about to eat her first ice cream, but a bird knocks it over. Then her family makes her a sundae so she gets to eat her first ice cream anyway.
- My Little Pony: Friendship Is Magic: Twilight Sparkle gets hit with this in the Season 7 episode "Once Upon a Zeppelin," where she and her family take a zeppelin-cruise as a way of getting away from her royal duties so they can spend some quality time together. Twilight's been especially looking forward to witnessing the rare Northern Star passage which takes place at sunset, but due to getting repeatedly and unwillingly roped into fulfilling a lot of events for fans thanks to the machinations of Iron Will, by the time she finally manages to get away, she's just missed out on seeing the Northern Star. Not helping matters is the fact that the rest of her family, who got to see the star's passage, start gushing to her about how incredible it was; at that point Twilight snaps.
Twilight: Oh, yeah, the cruise ponies are happy, my family is happy, even Iron Will is happy. You know who isn't happy? ME!
- One episode of Rugrats has a circus come to town, only for Angelica to catch a cold...then the babies pretend they've caught her cold since they don't want her to be the only one left out. However, they still get to watch the show on TV.
- The Simpsons: One episode has Bart and Lisa eagerly looking forward to watching a special episode of The Itchy and Scratchy Show, where Scratchy will supposedly finally get to kill Itchy. However, right at the pivotal moment, the TV gets plugged out... and when it's plugged back in a few seconds later, the episode is already at the end credits.
Krusty the Clown: WOW! They'll never let us show that again! Not in a million years! [laughs]
Bart and Lisa: AAAAHHHH!