In general, a Game Show contestant hitting a Whammy in a Golden Snitch or All or Nothing situation tends to result in this trope. However, a couple shows deserve special mention because they're set up to make this happen so often, it has to be an intentional budget-saver:
The British show Golden Balls consists of nearly an hour of bluffing and random money distribution to determine the size of the pot and to eliminate 2 of the 4 contestants. At the end, the two contestants left each have to decide whether to share or steal the prize fund. The rules Full explanation If both share, they split the pot 50/50. If one steals and one shares, the one who steals gets the entire pot. If both steal, the pot is lost and both leave empty-handed. give zero incentive whatsoever to share, and if both players opt to steal (the only Nash equilibrium in the decision table), then nobody wins a single quid, and the entire hour was moot.
Another British show, The Million Pound Drop, and its American spin-off Million Dollar Money Drop, after taking most of an hour with plenty of Padding to go through about 7-10 questions, require players to answer a final question (which they cannot opt out of) to win anything at all. The final question is multiple choice with two answers to choose from; if the players pick the correct one, they keep their winnings, and if they pick the incorrect one, they lose all their winnings at the very last second and they leave with zilch. The final question is always an Unexpectedly Obscure Answer which may as well be a coin flip, leading to many teams taking a considerable sum of money into the final question only to lose it.
Also from Britain was the very short-lived (canned after 4 episodes) Shafted, which ended with the two winners facing the same Prisoner's Dilemma as Golden Balls, mentioned above.
Take It All on NBC also ended with a "Prize Fight", which was the same old Prisoner's Dilemma.
The Price Is Right: An unintended example happened in this unique pricing game, which paired a studio contestant with a viewer who was playing at home (via a telephone hookup). The objective of the game was for the at-home player to give a price (from a list of seven) to the studio contestant, and for the studio contestant to pair it up with what he/she thought was the correct product; this process would repeat three times, before cash awards were announced, with up to $15,000 available to be split. Giving the name of a product would cause that contestant to lose a turn. More than once, teams have lost one turn before realizing the mistake and then the other two turns played as normal but the Shaggy Dog was in the audience the day a home viewer who likely did not grasp the concept of the game gave the name of the product on all three turns, leaving the hapless in-studio contestant with no money. The usual buildup was wasted on an irritated home viewer's inability to understand the game.
In a comedy/variety show from the late '70s, a little girl with yarn pigtails is sitting at the dinner table, refusing to eat her vegetables. Her brother, sitting adjacent, eagerly and proudly eats his veggies. There is then a montage of clocks advancing and calendar dates drifting by. After 11 years, the little girl is dressed the same, and still sitting at the table with the uneaten vegetables, as her mother is seeing her brother off to the Senior Prom. There were at least 2 more time montages, one of which implied that a certain fast food chain sold hamburgers by the billions, trillions, and now zillions! At the end, the little girl has aged considerably (same costume!), as a lawyer is reading a will, The girl is bequeathed the house and $4 million — but ONLY if she eats her vegetables. As before, she says she can't eat them. The lawyer then asks her WHY she can't eat her vegetables. The girl politely points out that she doesn't have a fork.
Mary from 227 once called Lester's boss when he'd gone a long time without a pay raise and left a scathing rant. Shortly after Mary leaves the message on the boss' answering machine, Lester comes home and announces he got the raise. Mary then sneaks into the boss' house to delete the message and they have to pose as the entertainment for the boss' child's birthday party. The boss later comes home and catches them in the act. Mary explains the situation and the boss says he understands...and that he doesn't have an answering machine.
The search for a virus that occupies much of the first third of Season 3 of 24. The virus was a decoy. Also, Jack's jailbreak was all part of a sting operation against the Salazars.
Played for Laughs in the According to Jim episode "Spelling Bee", where Jim and Sheryl take Gracie to places to compete for her Spelling Bee matches, which exhausts Jim and Sheryl. Near the end of the episode, Sheryl discovers that the only reason Gracie even bothers going through with these tournaments is because she gets to eat fried shrimps, at which point Sheryl convinces Gracie to throw the match, on the promise that Gracie doesn't have to win just so she could have fried shrimps. Gracie agrees before going on stage (with Jim chanting "lose, lose, lose" in a whisper and Sheryl muttering "it's just not your night" to herself)... and then the announcer reveals that the Spelling Bee grand champion will be given one year worth of fried shrimps as prize.
In season 15 of The Amazing Race, Zev and Justin started the fourth leg in eighth place, but ended up putting in an impressive showing and finishing in first place for the first time. Then they went through their belongings and discovered that Zev had lost his passport. They were unable to find it before the last team checked in and Phil was forced to eliminate them.
"Top Banana" has Michael trying to find some extra cash to keep the Bluth Company afloat. His father only responds to his plea with "There's always money in the banana stand." Michael also tries to find the flight records for the company to find out what his father's been up to, only for the records to have been burned. It's implied (and later confirmed) to be the work of a recently released arsonist Michael's father befriended in prison. Later, George Michael is overcome with the stress of running the banana stand and threatens to burn it down. Michael decides to help him so they can collect the insurance money. But then, two problems with this occur: 1)it's revealed that Gob deliberately refused to mail the insurance check, so they have no insurance on it and 2)when Michael's father told him "There's always money in the banana stand", he meant it literally.
"Sad Sack" has the FBI discover Michael knows where his fugitive father is. At first, they're unable to force him to reveal his location, but then they discover a picture in the Bluth Company database which apparently shows the locations of WMDs in Iraq. The picture seemingly proves a connection with Saddam Hussein and a justification for invading Iraq. The FBI gives Michael an ultimatum: surrender his father (who claims innocence) or go to prison in his place (when he's clearly guilty of much more). Michael spends the episode debating his choice, then goes to present it with their lawyer Barry. That's when Barry sees the picture for the first time and discovers something no one else noticed: the picture is actually a close-up of Tobias' genitals. The FBI promptly drops the ultimatum and the army cancels the invasion.
In Auction Kings, when a piece comes in that is expected to sell for much more than it goes for. Paul is quick to point out that the buyer is certainly happy though.
Unless a reserve is not met, in which case the seller is stuck with the piece, Paul gets no money and the buyer doesn't get the piece.
On Babylon 5, the character of Talia Winters was set up for a big arc from the first season. Kosh copied her fears, she was granted telekinetic powers, and she was growing increasingly disillusioned with the Psi Corps. When the actress wanted to leave, they wrapped up the "implanted personality" arc in one episode where her only significant role was in the last 10 minute "big reveal". She was then Put on a Bus and was never heard from again, except for the implication she was killed off screen. This one's a big case of Real Life Writes the Plot: Talia's actor, Andrea Thompson, had recently divorced Jerry Doyle (who played another major character, Michael Garibaldi), and was being offered a much juicier gig on JAG. She dropped out, and Talia's arc (except for the relationship with Ivanova) was picked up by Lyta Alexander (who had been established in the Pilot Movie but hadn't joined up for the first season over some contract dispute).
Batwoman played up several major storylines for Kate Kane from her father hating her costumed persona to her struggles to be accepted and even named a cosmic "Paragon." Then Ruby Rose left the series after its first season with new character Ryan taking over as Batwoman and thus rendering all of Kate's adventures almost meaningless.
In the Bones episode "The Bones on the Blue Line," Sweets meets a young man on the Metro who gets an email saying that, after eight years of chemo, he's finally cured and is going to begin living his life to the fullest. Then there's a flash flood and he's killed instantly in front of Sweets' eyes.
Bunk'd: In "Waka, Waka, Waka!", only Ravi and Tiffany are aware of the legendary Kikiwaka's existence, but nobody believes them, not even Zuri, who spent the previous episode being duped. To prove themselves, the two lure the Kikiwaka to them and Tiffany captures proof; however, she accidentally held her camera the wrong way, and she only got themselves instead, leaving them more humiliated than before.
In Season 6 of Castle, a few episodes revolve around Castle and Beckett getting what they need for their wedding (date, dress, venue, etc.), only for a number of random incidents occurring in the season finale to ruin them all, forcing them to use alternate plans. And then Castle disappears at the very end.
A summoner spends the entire episode working on a spell that would bring back a very powerful Big Bad from earlier seasons, the Source. It succeeds, but then Piper hits the summoner with her power three times and both the summoner and the summoned Source are vanquished. In less than two minutes.
In the 1st season, there was an episode in which they meet their male counterparts, supposedly as powerful as they are, only evil. They died in the last 30 seconds of the episode.
Played for Laughs when an Eastern European hockey player enters the bar and Sam tells Diane the story of how he got to America. He details all of the trials and tortures the man had to go through to get out of the Eastern bloc which awes Diane, then Carla ads "The following week, the rest of his team flew over on the Concorde."
One of the "Bar Wars" episodes (where they face off with Gary's Old Town Tavern) had them perform a retaliatory prank on Gary's when they seemingly steal Tecumseh (the wooden Indian) despite a peace agreement. It then turns out that Rebecca actually had Tecumseh taken away to be varnished. While the gang waits in fear of what Gary does, they get an idea to prank themselves. Just after they do that, Rebecca tells them that Gary's was closed the night they performed their prank and he didn't know they did that.
"Digital Exploration of Interior Design" ends with Vice Dean Laybourne inciting a war between best friends Troy and Abed (fought with pillows). Troy wants to go for a record for building the world's biggest blanket fort while Abed just wants to challenge himself by building a large pillow fort. The following episode "Pillows and Blankets" details the pillow war which ends up involving the entire student body. Near the end of the episode, a massive pillow fight breaks out between the two sides which is stopped by Dean Pelton blowing a whistle and making the following announcement:
Well, that's it! I just heard from the Guinness rep. He's not coming. He's been fired in what he's called the world's biggest mistake. I doubt that will make the next edition. Anyway, it's over! What a colossal waste of two and half days!
Briefly occurs in "G.I. Jeff" where Jeff falls into a coma and dreams he and the other study group members are part of G.I. Joe. After Jeff's group is thrown into the stockade, Cobra attacks the base. Another prisoner reveals that he's been digging an escape tunnel over the last few months and he's now ready to use it. Before anyone can go in, an explosion blows a hole in the wall and everyone escapes that way.
"Intro to Recycled Cinema" sees Chang become a celebrity after appearing in a series of popular commercials. Then Abed reveals he started to film a movie with him and the group decides to complete it and cash in on Chang's success. They meet a producer who suggests changing the film's genre (a crime drama to a space opera) and somehow stretch out his brief scene to an entire movie. When it's time to try marketing it, the producer calls his company and discovers they've declared bankruptcy. They also discover Chang has soiled his reputation in Hollywood, killing his career and ruining any chance of cashing in on him.
"Basic Lupine Urology" has the study group bring a classmate to trial to keep from losing a decent grade in Biology. They succeed, but the end of the episode has them receive a phone call that Starburns died as a result of a meth lab explosion. Their Biology teacher helped him with it and resigns out of remorse, resulting in the class getting cancelled and the trial becoming moot. It gets worse when the season finale reveals that Starburns faked his death, so their teacher quit his job and got the class cancelled for nothing.
"Intro to Political Science" has the college hold a class election when they discover that the vice-president is planning to visit. One of the Secret Service agents takes a somewhat romantic interest in Abed during the election. The election itself involves a lot of insults, glory-seeking, and general chaos. Plus, the Secret Service agent has to leave due to there being no credible threat at Greendale. The plot ends up a Shaggy Dog Story in two ways: First, the election ends with a very low turnout and the winner by write-in is South Park. Second, Abed makes a comment during the election coverage that implies the presence of a threat at Greendale, resulting in the vice-president cancelling his visit but the Secret Service agent staying to observe Abed.
"VCR Maintenance and Educational Publishing" has the Save Greendale Committee find a stack of old textbooks they believe they can sell for profit, resulting in a heavy deal of betrayal. Also, Abed and Annie get into a contest to decide who their new roommate will be, Abed's girlfriend or Annie's brother, which they plan to decide using an old VCR game. Both plots turn out to be meaningless. The books the group fought over are misprints with no page numbers and not worth anything, meaning the group turned on each other for nothing. Meanwhile, Abed's girlfriend is embarrassed by the spectacle of the game and leaves him while Annie's brother has no intention of moving in with them. At the very least, Abed is able to patch things up with his girlfriend.
Used in-universe in and episode of Criminal Minds in which Reid, trapped in a room with a death row inmate intent on killing him, essentially tells him a long "Shaggy Dog" Story using medical and psychological terminology in order to explain the criminal's violent behavior. Reid manages to run out the clock and is let out of the room when the guards at the prison change shifts. As he's leaving the room, the criminal asks him if it was all true. "I don't know. Maybe."
CSI: Ending Happy features a dead guy who five other people attempt to murder in a single night, but it eventually turns out that he died accidentally due to a lawn chair collapsing. To elaborate, in one night, this one guy gets... stabbed in the calf with a syringe full of snake venom twice. Gets an anaphylactic shock due to coming into contact with shrimp, which he's allergic to - via oral sex. Gets a crossbow arrow shot through his neck, which - funnily enough - opened his airway from the previous anaphelactic shock. And finally falls into the pool, drowning... maybe. He might have already been dead when the chair collapsed and he fell into the water.
"The Parting of the Ways": The elaborate battle plans and resistance that most of the episode focusses on hardly slow the Daleks down when they invade the Gamestation. Earth is bombed hard enough to deform entire continents, everyone on the station apart from the Doctor is massacred by the Daleks, and the Doctor can't go through with destroying the rest of humanity to stop them. Only the arrival of BadWolf saves the shaggy dog from being shot.
In "A Christmas Carol", much of the story revolves around The Doctor mucking around with the timeline note (your mileage may vary as to whether this violates the spirit and premise of the show) in order to give Kazran a change of heart and save the day. It turns out Kazran hasn't the means to save the day (he actually did before the timeline was mucked with), so an entirely different solution is substituted at the last minute.
The most prominent example would be the murder of Ennis Stussy, which was completely accidental (the killer confused him with a namesake, Emmit Stussy). Nonetheless, the police found out that Stussy used to be a talented sci-fi writer Thaddeus Mobley in his young years, and believe that the murder could be related to his past.
This leads up to episode 3, in which Gloria goes to Los Angeles to investigate Thaddeus' past life in the 1970s, and finds out some dark secrets, but eventually understands that it's completely unrelated to the murder: "No. Its just a story. None of this has anything to do with [the murder]". Basically, the whole episode has a Red Herring theme through it, with a number of bizarre occurences that eventually amount to nothing, like a man dressed up as a Santa Claus' elf who steals Gloria's luggage and a strange box with a button that she finds in her hotel room whose only function is to turn itself off when you press the button to turn it on. Finally, there is story of Thaddeus Mobley's novel The Planet Wyh, which runs as a parallel plotline, and tells about an alien robot who stayed on Earth for millions of years, witnessing the rise and fall of civilizations... but when he was finally recovered by his alien creators, they simply told him to turn off.
Another example is in the episode 2, when Nikki burgles into Emmit's house to get the stamp and finds the donkey picture in place of it. Emmit replaced the stamp with this picture completely by accident, but Nikki figures out that he did so deliberately as a way to mock her and Ray. She also finds a bank deposit number, and, believing that the stamp is here, she and Ray concoct an elaborate plan to break into it... What they eventually find in the deposit box is the ashes of Emmit's beloved deceased dog.
In an episode of Father Ted, Dougal asks Ted if he's ever seen a ghost. Ted starts telling a story of how he was staying at his great-aunt's spooky old house in the middle of nowhere, and was staying in a bedroom where a heartbroken girl had allegedly hung herself many years before. He describes how the room was icy cold, lit by a single candle, and then suddenly he heard a creak.
Dougal: Was it a ghost? Ted: No. So no, I've never seen a ghost.
The Joey-Rachel relationship in Friends. There's a few episodes centering around Rachel secretly having feelings for Joey. The cliffhanger of Season 9 has Joey and Rachel kissing. In the first two episodes of Season 10, there's some serious drama about how Ross will feel about the whole thing. And the episode after that... they decide they're better off as friends. The fact that they even went out at all is only mentioned once in the rest of the season. Partially Real Life Writes the Plot as the final season was six episodes less than the others due to Jennifer Aniston's condition of returning only with a shorter season in order to pursue her film career.
The Fresh Prince of Bel-Air once had Will play a game of poker against Jazz and another guy while telling him the story of how he and the family were forced into Witness Protection. He explains that a hitman came after him and he got the locals to defend him, only for them to get drunk and pass out. Will says he's going to tell Jazz how he got out of that after Jazz buys into the next hand, but Jazz is out of money. It turns out the story was Will's way of distracting Jazz from playing the game to his best.
The fifth season revolved around Will's relationship with his fiancée Lisa, and the Season Finale was their attempt to get married. However after the two realize they don't know each other as well as they thought, Will attempts to move past it but Lisa leaves him at the altar and is never seen again.
After a whole season of building his own power and defending King's Landing, Tyrion faces a Bodyguard Betrayal. By the time he recovers, all his accomplishments and alliances have been lost or claimed by others, leaving him back where he started.
Tyrion tells one while awaiting his trial by combat. He describes in great detail his fascination with his simple-minded cousin crushing beetles, but the story peters out without any resolution. The implied meaning is that suffering happens for no greater reason than a simpleton smashing bugs.
Daenerys is tragically driven Ax-Crazy by a combination of backstabbing / dying supporters, dead children, constant failures, wilting self-esteem from learning of her status as the spare heir, and of course, surprise incest. Mere moments after Westeros surrenders unconditionally, Dany orders her armies to purge King's Landing. There's a single hope spot as Grey Worm has stuck by her side through most of her conquest and has been The Stoic through all their battles - and then he starts ordering the Unsullied to help the Dothraki organize the purge. Naturally, the city and the armies are dismantled as Daenerys is assassinated before she can continue her plans for World Destruction, and after the nobles seemingly elect a Puppet King, the Seven Kingdoms slowly transition from an empire to The Federation. Everything Daenerys did to free the world ended up enslaving and killing it, and only after she was defeated did it finally begin to free itself.
In one episode Richard and Emily are drawn closer as they try to find the owner of a stray dog that had happened upon them, leading the audience to expect that the experience will lead them to end their separation. In the end, though, the dog's owner claims it and it's back to status quo. The only real revelation to come from the affair is the gender of the dog, which was not what they had thought — it was a very shaggy dog.
Also Jess's return in Season 6. He appears again having reformed himself, he and Rory clearly still have feelings for each other, they kiss and... she goes back to Jerkass Logan. Not a complete shaggy dog story as he was the catalyst for Rory fixing her life but the relationship between him and Rory (building since Season 2) goes nowhere.
The Hurricane episode of The Golden Girls had Rose organize a telethon to raise money for an old lighthouse to be preserved and added to the National Register. When the hurricane comes, the telethon's guests cancel their appearances and the lighthouse is destroyed.
The Hard Times of RJ Berger features an episode titled the Berger Cometh, in which RJ gets a part in a play to get closer to his love interest, Jenny, finding out that the play will feature a kiss between them. His best friend warned him not to star in another play, considering his past experience in an elementary play, where he had one line, but messed up, soiled himself, and having the audience laugh. In this one, RJ is afraid that things will mess up for him, and he will be humiliated again, because he has an erection. His best friend thinks, foolishly, that it will be all and well done if he puts scotch tape on the penis, so he does. Turns out, before RJ and Jenny do end up kissing, the scotch tape comes off and the erection is illuminated on the wall, and RJ having the large penis that he does makes the situation all the more hilarious, and the audience laughs again, and Jenny walks off the set in embarrassment, so basically it was all for nothing. At the most, Jenny does apologize to him for storming off, and RJ's parents do reassure him that though he is not a normal kid, he is extraordinary and they could not be prouder.
Head of the Class once had Dennis get into a food fight over the quality of the cafeteria food. Afterwards, Mr. Moore introduces him to the student protests of The '60s. This inspires Dennis to stage a sit-in at the cafeteria for fresh food without preservatives. He also asks for a salad bar and amnesty for his fellow protesters. Mr. Moore takes his demands to those in charge and comes back to report that they agreed to...only the salad bar. Dennis at least takes in this small victory...until he remembers that he hates salad.
In the Henry Danger episode "Text, Lies, and Video", Charlotte films Ray and Henry transforming into Captain Man and Kid Danger on her phone and the video accidentally gets sent to Piper. Henry does everything to delete the video off Piper's phone before she sees it, including having Jasper try to steal the phone (which he fails to do), destroying her phone, and trying to steal Piper's new phone after she uploads all her back-up data. After the video is finally deleted off her phone, Henry, Ray, and Charlotte decide to watch the video, only to discover that Charlotte had filmed herself instead of Henry and Ray. Charlotte even lampshades that the whole thing was a waste of time.
Charlie's little sub plot in Season One. Hiro witnesses her die brutally, so he goes back in time six months to prevent the whole thing. Several months take place as the two of them fall in love. When Hiro tries to tell her that she will die, she tells him that she has a blood clot in her brain and will die shortly anyway. Oops. Waste of six good months.
It's also not that much of a Shaggy Dog story if you read the novel Saving Charlie, where the relationship is developed further. Also, Hiro's "accidental" teleports keep carrying him back to the task of saving Claire Bennett and Charlie eventually calls him on the fact that Hiro is neglecting his destiny just to spend time with her. That doesn't stop the two of them from losing their virginity to one another on the night before Charlie is supposed to die though.
Of course that wonderful story was tossed in the garbage and this really DID become a Shaggy Dog story as of Volume 5 when Hiro went back to save Charlie and was successful. He somehow managed to get his past self to go back in time to fall in love with Charlie, get Past Ando to hang around until Past Hiro gets back AND talked Past Sylar into using his powers to cure Charlie's blood clot (Don't Ask)... only to have Charlie get "lost in time" by this Volume's Big Bad! And when Hiro meets Charlie again in the present, she's old and asks Hiro not to go back in time, because she's built a family during 65 years and doesn't want to lose that. Doubleyoo. Tee. Eff.
The season one finale "Come On", ended with Ted coming back to his apartment and finding Marshall, engagement ring in hand, as Lily had broken up with him to go to an "art fellowship" in San Francisco. Since it was a Foregone Conclusion that the two would end up together, Lily's art fellowship thing petered out for no particular reason. Why needlessly make Marshall angst for six episodes?
This issue comes back in Season 9 where Marshall and Lily have an argument about their jobs (Lily has to go to Italy for her art career while Marshall accepts the position as a New York judge without consulting Lily about it). It is revealed that Marshall hadn't forgiven Lily for leaving him to San Francisco. While this arc presented their hardship on their marriage, their whole problem is resolved very quickly when Marshall discovers that Lily is pregnant with their second child and he decides to go to Italy with her instead.
The Barney/Robin romance also falls prey to this. After an entire season of Barney pining silently over Robin after a Love Epiphany, involving a lot of Character Development for both of them, they finally get together... and break up seven episodes later over almost nothing, to allow Barney to revert back to his whorish ways and Robin to revert back to her commitment-fearing, career-driven lifestyle.
This actually gets revisited/resolved in later seasons as it's revealed that Barney and Robin end up getting married. Meanwhile, both of them undergo much character development, growing up and becoming less commitment-phobic. And then after three years of build-up from the reveal in Season 6 that Barney was getting married to finding out in the season 7 finale that it was Robin the whole of Season 8 bringing them together and having Season 9 focus on just their wedding weekend and how far they have come and are going to make it work, they get divorced 3 years later. Not three seasons later; right after we're done with the wedding, the series finale has them divorced. Barney goes back to his man-whore ways until he has a daughter. The mother who we have been waiting to meet all this time? She's dead, and Ted hooks up with Robin.
Pretty much every girl that Ted falls in love with and hooks up with. Particularly Robin. We know right from the first episode that Robin is not the mother but a large part of Season 1 and 2 and in a few other seasons is dedicated to Ted pining over Robin, Robin pining over Ted, getting together and breaking up, thinking of restarting their relationship, having a no-strings-attached relationship and then deciding they are Better as Friends. And that particular resolution turns out to be for nothing thanks to the finale.
In-universe, there's an episode where Marshall, Lily and Barney spend the entire time trying to guess which Canadian celebrity invited Robin over to look at which collectible and propositioned her to engage in which sex act. At the end, she finally tells them. They probably would have been more impressed if they had known who The Frozen Snowshoe was, what Harvey's trays were or how one performs an Old King Clancy. And then, the audience is shown that Robin was being an Unreliable Narrator anyway.
Both plots in "iSpaceOut". Carly gets Space Madness and the trio lose the chance to go into space, whilst the mute freaky little girl that spooked Spencer just leaves without talking or any explanation about who she is or where she came from, except that Carly could see her ruling out the previous ideas of a hallucination or vision from Spencer.
"'iBust A Thief" spends an episode on the plot of a stolen laptop. In the end the so called 'thief' of the laptop didn't steal it (wrong colour, and Sam wrote the serial number incorrectly). The end is Sam finding her laptop in a pizza box in the fridge.
It's Always Sunny in Philadelphia: "America's Next Top Paddy's Billboard Model" is this from the perspective of the modeling contestants (especially the ones who had a threeway with Mac in order to win). The winning model's prize was supposed to be a place on the bar's new billboard, but it turns out that before the contest even began, Frank had already put the billboard up with himself on it.
Many episodes of the series end like this with the Gang's efforts amounting to nothing, oftentimes due to their own ineptitude.
Notable is the Cheese Shop sketch, wherein a man enters a cheese shop and rattles off several kinds of cheese he wants to buy, only for the store owner to tell him at the end of the sketch that the shop, in fact, doesn't have any cheese at all. Another is the audio-only Book Shop sketch, wherein a bookstore owner gets increasingly frustrated and desperate to find a book that a customer will buy. The owner finally finds one the customer wants, but the customer doesn't have a way to pay for it. So the owner buys it for the customer... but the customer can't read.
Possibly the most famous episode is where The Colonel stops sketches for getting too silly, including the famous "Dead Parrot" sketch.
Another example — which actually originated in the one-off pre-Python special How To Irritate People, but was retooled for this series — is the "Silly Job Interview" sketch, where a job interviewee is put through an increasingly ridiculous set of questions and tests, finally causing him to snap and give the interviewer a "The Reason You Suck" Speech. This, apparently, is what the interviewee was meant to do all along... not that it really matters, since the job vacancy had been filled weeks earlier.
Law & Order frequently uses serious shaggy dog stories, where the suspect avoids being convicted only to be caught for another crime, dying unexpectedly (and sometimes spectacularly), or otherwise being punished by the forces of Fate. Also, frequently the controversial issue of the day which the defense attorney's scheme is hinged around ends up being irrelevant when a simple, personal motive appears in the last five minutes.
New characters Nikki and Paolo from season three of Lost turned out to be one big Shaggy Dog Story; after an entire episode spent setting up their circumstances and motivations, they are killed off (horribly) before they can affect the plot in any way. This is mostly the viewers' fault, though- they'd been planned to be more important but nobody liked them so they were quickly written out.
Depending on who you talk to, the show has quite a few examples, up to and including the entire thing.
The Mad About You arc where Paul shoots a documentary on his family hits a snag when one relative dies during an interview, muttering "Who... Moos" as he collapses. Paul then makes an investigation into his last words, launching a Whole Plot Reference to Citizen Kane. The resulting investigation ends up causing several rifts within the family. At the funeral, another relative reveals the last words were a reference to an incident from their childhood and asks them to put their differences aside for the sake of the deceased. Satisfied, the family leaves the funeral on good terms and Jamie looks at the camera Paul used to film. She notices it says "HOO MOO5" on the lens.
TheMandalorian This takes some Fridge Logic: The second season has Din deliver Grogu to Luke. The Sequel Trilogy states Ben killed all of Luke's students, presumably including Grogu, rendering most of the plot of The Mandalorian pointless.
In-universe example: A throwaway joke in one episode has Hawkeye verbally constructing a fantasy for BJ involving the latter (in a smoking jacket with a zipper down the back) and Lana Turner (in a pink angora sweater with a zipper down the back).
Hawkeye: She throws her arms around you, but you push her away! BJ: ...I pu-I push her away? For what? Hawkeye: Your smoking jacket is covered in angora lint. In a fit of pique, she leaves. BJ: ...That's it?! The end?! Hawkeye: That's it. BJ: But what about the zippers down the back? Hawkeye: They didn't catch on.
In the episode "For Want Of A Boot", Hawkeye goes through an elaborate Chain of Deals to acquire a new pair of boots. At the end of the episode, the entire chain collapses like a series dominoes, making it so all of Hawkeye and Trapper's efforts were for nothing.
Another, later episode is about a Chain of Deals, this one about Radar trying to get tomato juice for Colonel Potter after hearing he loves it so much. This time, Radar succeeds, but again, it's all for nothing, because by the time he finally gets it, Potter's remembered that although he loves it, he's allergic to it.
In another episode, after being sick of having the same thing at the mess tent every night, Hawkeye goes through a long, complicated process simply to have spare ribs delivered from a certain place in the States, and finally gets them, only for wounded to arrive just as he and the others are about to eat them.
Once, Hawkeye and Trapper go to elaborate lengths over the course of an episode to get some R&R in Tokyo, only for wounded to arrive just as they're packing.
An episode of Murder, She Wrote had Grady Fletcher staying at Jessica's home while she was out of the country, only for a murder in the home to pull him into the schemes of several competing treasure hunters who were seeking an extremely valuable ancient artifact that had somehow been gifted to Jessica years ago. Turns out that the murder was committed during a conventional burglar who knew nothing about the artifact. At the end, Grady is in the police station with the treasure hunters only to accidentally drop and destroy the priceless artifact... and then his wife notices that "MADE IN TAIWAN" was stamped at the bottom. However, town doctor Seth Hazlitt notices that a key fell out of the broken object, implying that a real treasure remained to be found. Once one of the treasure hunters suddenly swiped the key and ran off, and the other two chased after him, Seth revealed that the key was to his old fishing tackle box and that the trio would be kept busy for some time by it.
Mystery Science Theater 3000 had a host segment during the episode where they watch Bloodlust where Mike and the bots put on a murder mystery game. Apparently, the whole thing took a while to set up with them getting dressed up in costume and laying out the clues. Unfortunately, Crow's enthusiasm gets the better of him and he yells "I did it!" literally as soon as the game starts.
NCIS's episode "SWAK" has a character contract a variation of Yersina pestis (bubonic plague). They spend the entire episode running around trying to find who did it and why, so they can get a cure, only to eventually find out that there is no cure. However, one wasn't needed; it had a suicide gene, and killed itself off anyway, so what they were doing in the meantime treating the symptoms... was actually the only treatment necessary. To make matters even worse, the whole affair happened because a mother wanted NCIS to reopen her daughter's rape case, only for the daughter to admit at the end that she made up the whole story.
The Nova episode "B-29: Frozen in Time" follows a team that spends months trying to repair and recover a B-29 Superfortress that made an emergency landing in Greenland in 1947. One guy actually dies working on it. They get it started and moving and... the damn thing catches fire and burns to the ground.
A two-episode arc of Power Rangers RPM focuses on Tenaya 7 trying to steal a rare diamond to power up her Monster of the Week, which she claims will ensure easy victory for Venjix. Even though she does steal the diamond, the Rangers destroy the monster in their Megazords within 10 seconds without breaking a sweat.
The whole first season of the Spanish series Los Protegidos ends up being a big example of this. The Big Bads of the season turn out to be good people who are also protecting a superpowered kid. And then they leave the series. The true Big Bads don't start appearing until Season Two.
Another episode has Shawn and Gus go undercover at a modelling agency after a fashion mogul and his wife are murdered. Shawn barely fits in, but Gus is easily accepted as a model and starts to neglect the assignment. During the investigation, Shawn discovers that the mogul and his wife murdered each other and reveals this. In the process, he outs Gus as not a model, souring their friendship, and with no one to arrest, the case ends on a whimper.
In "Queeg", Lister tells Rimmer a story that at first seems to be a serious example of why it is cruel to give machines personalities. He discusses a pair of artificially intelligent shoes that are discontented with their existence and try to escape it by stealing a car. They then accidentally drive it into a canal and "die". A priest, however, comforted the shoes owner by telling him that the shoes had gone to heaven. Turns out the entire lecture was just an excuse for Lister to deliver the Incredibly Lame Pun "Shoes have soles". Rimmer, however, doesn't get it.
Rimmer: What a sad story...Wait a minute. How did they open the car door?
The same episode: After endangering the crew, Holly is set to be replaced by the more efficient but completely domineering back-up computer Queeg. Hilarity Ensues. However, after losing a battle of wits and apparently being erased, Holly tells them it was all a prank. Every single event in the episode was made up.
The eighth season in Retro Game Master featured a segment called Xevious Observation Log, where they turned on its God Mode cheat, taped both buttons down, and left it to run 24/7 for as long as possible to see what happens. Eventually, the score counter overran and began showing glitchy characters. At the end of the season, they kept it running by putting the setup under a cardboard box labeled "Keep Out". However, two seasons (more than five months) later, they return to it and find it shut off, due to a blackout that happened in the interim. Worse, the blackout was announced in advance and no one thought to check the Xevious game before then.
In season five of Royal Pains, Evan runs for a seat on the town council in order to undo a new ordinance that would force HankMed to close down. After many trials and tribulations, he somehow manages to win the seat, only to give it up after Hank's season-long drug issues force him to sell HankMed.
In another Season 4 episode "Fall Formal", Ryan spends the whole episode trying to get Eric to sing in the school dance after learning that a record producer will be a chaperone there, and he gets Eric to perform in the school dance late in the episode, intending to get Eric discovered with Ryan himself as Eric's manager. When Eric shows signs of stage fright upon realizing a record producer will be present, Ryan tricks Eric into believing said record producer won't be there after all, which succeeds in relieving Eric of his stage fright, and, determined to make sure Eric doesn't lapse into his stage fright again, asks Screech to help keep the record producer hidden out of Eric's sight while Eric performs. The problem? Screech spends the same whole episode looking for someone to fix the broken air conditioner in Mr. Belding's office, and he sends the record producer into Mr. Belding's office for the repair once he finds out that said record producer knows how to do it, the result being that the record producer ends up repairing the air conditioner, injuring his hand in the process, throughout Eric's entire performances, meaning that, while Screech DOES manage to keep the record producer out of Eric's sight while Eric sings, it also means that said record producer never gets to hear Eric's performances at all, much to Ryan's immense dismay.
Maria and Liz spend the entire time in the Season 6 episode "The Lyin' King" vying for the attention of an aerobics instructor, going so far as to join his aerobics class sessions, only to find out at the end that he has a personal standard against being romantically involved with any of his students, past or present.
Liz: We killed ourselves for nothing.
Maria: Let's hit the whirlpool...
Liz: ...and then grab ourselves a big, fat cheesecake.
The Scrubs episode "My Princess". Dr. Cox tells his son a story about a patient from that day, but as a fairy tale. The patient is referred to as a maiden who is being attacked by a monster who cannot be killed, and the entire episode is about JD and Elliot's search for a cure for her. At the end, Cox tells his son when asked that the "maiden" lived happily ever after - only to walk out and strongly hint to his wife that in reality the girl died.
Lampshaded in the SCTV sketch, "Bad Acting In Hollywood". The movie within the Show Within a Show, which is about a gangster on trial, ends with the announcement of the attack on Pearl Harbor. The D.A. states that he and the defendant will now be fighting on the same side.
One episode details Kramer's quest to return a pair of pants. However he falls on the way, ruining the pants (which he had worn). Elaine later asks what Kramer was planning to wear back after he returned the pants, but as a Cloud Cuckoolander, he doesn't understand the question.
Another episode had Kramer get a strongbox and start playing with it. He puts Jerry's new cuff links in it, locks it, and hides the key. A few days later, Jerry runs into a pair of his neighbors coming home in tears because their pet bird Fredo died. After they go back into their apartment, Kramer reveals he hid the key in Fredo's cage and he must have died after eating it. Now, Jerry and Kramer have to dig up Fredo's grave to retrieve the key and Jerry gets caught in the act by the neighbors. Afterwards, Jerry is about to open the strongbox to retrieve his cuff links, only for George to casually open it before they can unlock it.
Kramer: How about that? It must've never been locked in the first place. Jerry: Kramer, are you telling me that we just desecrated Fredo's grave for nothing? Kramer: Sure looks that way. Well, Jer. This is one for the books. Definitely one for the books.
Jerry spends one episode trying to get out of paying a fine for a library book overdue by several years, claiming he specifically remembers returning it. To prove his innocence, he tracks down the girl he was seeing at the time who was a witness to his returning the book. Through several inconsistencies between her story and Jerry's supposedly vivid memory, he realizes that he misremembered the whole event. He never returned the book after all; he gave it to George, who lost it.
Jerry's subplot in one episode has him fall asleep while watching television, wake up in the middle of a bad science-fiction movie, and hear a rather weird line of dialogue. Thinking the line was funny, Jerry writes it down, but is so drowsy that it comes out as meaningless gibberish. He shows it to everyone he knows, but they can't make it out either. Later, he sees the movie again and hears the line of dialogue he thought was so funny ("The flaming globes of Sigmund!") only to realize the line wasn't that funny.
The protagonist murders a man on a beach, and as the story unfolds, more and more questions arise as to why she committed such an act. A great deal of questions and mysteries are introduced, insinuating at several points that there is a subconscious trigger for her killing the man, which also causes her to violently attack a police officer determined to help her, similar to some form of Manchurian Candidate. However, after various revelations about her life and the life of the detective, his marriage falling apart, the officer takes her back to the scenes of the crime, and the reason is revealed to be a paltry case of accidental death in which a girl with a congenital heart defect dies during or shortly after sexual intercourse.
The episode "Move Along Home" has several main cast members struggling to escape from an incredibly lifelike game — only to eventually fail, and end up back in reality with no consequence except that Quark doesn't get to keep a bunch of gems he would have won from the aliens of the week. Said aliens are rather surprised at their relief to still be alive; after all, "It was only a game!"
Another example is the popular Bottle Episode "Duet". The whole episode is spent confronting the Cardassian war criminal Gul Dar He'el for his brutal actions during the Cardassian occupation of Bajor. Throughout the episode, Kira figures out that the Caradassian in custody is, in fact, Aamin Marritza, a humble file clerk trying to pose as Dar He'el to get Cardassia to own up to its actions. At the end of the episode, Kira releases Marritza, telling him that Cardassia needs people like him if it's going to reform, and the episode is all set to end on a happy note. Marritza is promptly stabbed to death by a Bajoran, who states that he only killed Aamin because he was a Cardassian.
On one episode of Taxi, Ascended Extra Jeff gets fired when he gets blamed for Louie's theft. Alex eventually guilts Louie into confessing to the boss... except the boss doesn't believe his confession, and yet is so impressed by Louie's "sacrifice" that he re-hires Jeff.
The Thick of It plays this for laughs at the end of the Christmas special "Rise of the Nutters". The Prime Minister had announced his resignation at the end of the previous episode and an expected successor was being prepared to be nominated in his place... only for rumours that another politician was planning to run for the leadership himself and has apparently gone into hiding, which created a whole tornado of counter-rumours, other possible leadership contenders, and general chaos as the characters try to maneuver themselves into positions of power, manipulate events to their personal advantage, or just generally try to figure out what the hell is going on. Finally, at the end of a sleepless night of chaos for all the characters, the politician who's rumoured leadership bid caused all the trouble has finally been tracked down... only to reveal that he privately assured the expected successor that he had his full support and isn't planning a leadership bid at all, rendering all the flapping about utterly pointless. And to add insult to injury, he'd spent the night asleep in bed at his home, and could have been found there at any time had anyone actually checked.
An example with a twist from The Torkelsons: One character is in a contest to spend time in Paris with a family. As would be expected, she loses. But it's how she loses that makes it a Shaggy Dog Story: She had the highest scores... but the French family wanted to have a boy spend time with them, and there was only one boy in the finals. Meaning the finals had been meaningless before they had even started (Which counts as a Crack Defeat as well).
The Two Ronnies' famous monologues by Ronnie Corbett in his chair. Ostensibly all about telling a single, usually only moderately funny joke, the real joy was in the meandering way he eventually got to the punchline over five minutes, wandering off on a variety of bizarre tangents in the process.
Victorious: The "Flour Bomber" plot in "Robbie Sells Rex" ends in an anti-climatic reveal that the bomber is some random kid from another school who was doing it because he was bored. He gets caught, everyone walks away after finding out.
In one episode of The Walking Dead, the group, on Hershel's farm, must clear a well of a rather disgusting bloated zombie. Unable to shoot it because its blood would infect the water supply, they are forced to perform a dangerous winch operation which almost costs Glenn his life. After noosing the zombie and taking great effort to pull him up and busting the water pump in the process, the zombie simply splits in half, sending its guts into the water and infecting the supply anyway. The group are...annoyed, to say the least.
The show legitimately used this trope in Season 1 Episode 3, where The Killer escapes and is explicitly inferred to have committed suicide after failing to recreate all of the Jack the Ripper Killings, which makes all of the team's work to catch them essentially moot, and irks Commander Anderson, who claims that there will be another detective put on the fast-track, and it won't be DI Chandler. Due to his issues with stress and demonstrated by his pleased expression at the end of the episode, it can be assumed that this new peace is what Chandler really wanted all-along.
This happens again in S2:E3 when spoiler: Jimmy and Johnny Kray are assassinated after it is revealed that they are not related to the infamous British Gangsters after all, destroying their lives. This could, however, be considered a "Shoot the Shaggy Dog" story instead, due to the suicide of one of the characters who turned-out to be a mole.
This was Lampshaded in almost every episode thereafter,, where the detectives go to great and comical lengths to bring someone in alive, and almost always fail, or the criminal dies very shortly after being captured (S4 E2, the criminal dies of advanced Ergot poisoning, and S4 E6, where the cult are killed in an prison-transport crash).
A semi-supernatural "Satan-figure" is even introduced to further the darkly-comical quest for a live capture, who does such things as tamper with the environment that the detectives work in (by sabotaging the water mains and fuse boxes) and is directly responsible, through supernatural-seeming methods, for the deaths of each of the preceding criminals.
Finally, the production of Whitechapel itself could be considered a "Shaggy Dog Story", as the show gets half-way through its plot arc, and the "Satan-figure" built-up and identified, and was subsequently cancelled by ITV, before any final ending could be developed.
Whose Line Is It Anyway? did this in one of their Improbable Missions. Ryan and Colin had to wash the Emir of Groovefunkistan's burnoose. They had to go through all sorts of things—climbing the outside of the hotel using Ryan's hair, dealing with a bomb on the faucet of the bathtub, the cat being wet, and so on. Colin had a spare burnoose the whole time.