One-Episode Wonder

There are two types of shows that last for a single episode — the ones that are immediately canned, and those that never get picked up in the first place.

The former category should be easy to explain — if a show gets extremely negative reviews, poor ratings, or contains controversial content without enough redeeming value to be worth dealing with the Media Watchdogs, it's likely it'll die a quick death without anyone caring...it's a wonder anyone thought the idea would work in the first place.

However, the second is intriguing — television pilots that never got sold. Now, certainly, many of them are poor to middling in quality, and this is to be expected. Still, there are those that slip through the cracks with an awesome premise, superb casting, and overall excellent execution to the point where you're wondering why it didn't get picked up. They're Screwed by the Network and Too Good to Last before they even get a chance to shine.

Until the internet, occasional anthology series would be the only place for these quirky bits of production history to be showcased.

See also Backdoor Pilot and Audience-Alienating Premise; compare to Stillborn Serial. Not to be confused with One-Scene Wonder. For characters who appear in only one episode of a series, see One-Shot Character.

Examples (more-or-less in alphabetical order):

Real Life One Episode Wonders

In early 2010, One Thousand Ways to Die aired a spinoff named 1000 Ways To Lie, based around common scams. Spike TV actually had 13 episodes filmed but chose not to air them after the pilot was so poorly received.
The Adventures of Superpup: At the end of the fifth season of The Adventures of Superman, star George Reeves was found dead. The producers of the show handled the situation in the classiest way possible....by filming an After Show pilot on the same sets with little people wearing giant dog masks, using character names such as "Bark Bent" and "Puppy Bite".
The Amazing Screw-On Head: 2006 animated pilot based on a one-off comic by Mike Mignola, creator of Hellboy. Featured Paul Giamatti as a Steampunk cyborg who fights paranormal forces at the behest of the Lincoln administration, with David Hyde-Pierce as his arch nemesis, Emperor Zombie. The Sci-Fi Channel actually had an online poll to gauge interest, but despite being very well-received it somehow never made it, possibly due to low numbers (ignoring how hard it is to promote a one-off pilot or attract word-of-mouth).
Anchorwoman: A reality show in which Lauren Jones, best known for her role as a WWE diva, gets a role on a local TV news station, acts like an airhead, and competes with an equally pretentious rival. Hilarity Ensues.
Aquaman: 2006 superhero show from Smallville creators Al Gouch and Miles Millar, though not intended as a spin-off. Was called Mercy Reef in the development phase.
Australia's Naughtiest Home Videos: 1992 Australian comedy series featuring videos of sexual situations and other explicit content (aka Animals Having Sex). Canceled a third of the way through its broadcast by Kerry Packer, executive of the broadcasting Nine Network, phoning the studio operators to order them to "Get that shit off the air!", and replaced with a Cheers re-run.
Babylon Fields: 2007 zombie drama. Rather than being portrayed as malevolent monsters, however, the recently deceased return to their homes and attempt to pick up their lives.
Battlestar Galactica: Blood and Chrome. Originally intended to be a new TV series, Syfy Channel later cut the order back to a TV pilot, then slashed it again to a low-budget webseries with all CGI sets, of which exactly one episode was filmed and then hidden away in the network's vaults. A trailer for the show surfaced in early 2012, which was later revealed to have been smuggled out of Syfy and leaked to the public without their authorization. Syfy says it has no plans for producing or even airing Blood and Chrome, because as everyone knows Syfy Channel only shows wrestling now-a-days.
Battletoads.
Biffo Vision, the sketch show by ex-Digitiser man Paul Rose, was shunted to "youth" channel BBC Three, as it took on the form of a decidedly twisted kids' show...who chose not to pick up the programme as it appealed to too old a market.
Bob and a Half: A horror series about a guy who finds his friend chopped in half.
Bubsy, which nobody would've ever seen if not for the fact that it was packaged with the Windows version of one of the Bubsy games. Rob Paulsen leaves it off his résumé nowadays...
Buffy the Vampire Slayer: The Animated Series. It never even made it to the full pilot stage, but the link is to the 4-minute promo on YouTube. It features almost the entire original cast (except Sarah Michelle Gellar; they got Buffy's voice from the video game instead).
The Clerks live-action pilot from 1995 with Jim Breuer.
Co-Ed Fever: 1979 CBS sitcom set at an all-female college that had just started to admit male students.
Constant Payne: 2001 animated pilot for Nickelodeon. Similar in concept to Jonny Quest, it followed the Payne family, consisting of an adventurous super-inventor and his daughter. There are several reasons why it didn't get aired.
Charlie Brooker's Gameswipe, a 2009 show about video games hosted by Charlie Brooker.
Dear Diary: Dreamworks production that eventually went on to win the 1996 Oscar for Best Live Action Short Film.
British "Nothing but Phone-in Game Shows" channel ITV Play had a very awkward one in 2007 with "The Debbie King Show"; hosted by Debbie King of Quizmania fame, which was part call-in news/talk show, part call-in quiz show. However, in response to a major scandal and investigation surrounding premium rate quiz shows, ITV had announced earlier on premiere day that ITV Play would be discontinued that same day. Somehow, they still went on with the show.
Dragon's Heaven was one single OVA based on an old, highly obscure manga, but with some of the coolest mechs ever and an awesome soundtrack, it's a crying shame that nothing more ever came of it.
Emily's Reasons Why Not: A comedy starring Heather Graham, based on a novel of the same name. It was intended to be the anchor of ABC's post-football-season Monday night lineup in 2006, and failed miserably, getting cancelled after its only airing in January despite heavy promotion during the fall of 2005. It was said ABC bought the series without seeing a script. It was cancelled so quickly that magazines that came out the next week were stuck running feature stories promoting a show that was no longer on the air because their press deadlines came before the airing of the one episode.
Fearless was officially placed on the 2003 Fall schedule by The WB, but later delayed to midseason (One Tree Hill appeared in its place) and then canceled without ever being broadcast. If you're curious, the pilot can be seen on YouTube in its entirety.
In 2000, PAX tried a Bible-based quiz show called Genesis, hosted by Jim McKrell.
Global Frequency: A 2005 Mark Burnett adaptation of the Warren Ellis comic book series, starring Michelle Forbes of Star Trek fame. According to Ellis, when the pilot was leaked onto Bit Torrent networks (to tremendous acclaim), The WB simply axed the project altogether.
Head of the Family: a pilot that featured Carl Reiner as the Head Comedy Writer for "The Alan Sturdy Show", and showed both his home and work life. The pilot was rejected by CBS and burned off as a one time "comedy special". Producer Sheldon Leonard saw it, completely recast it, changed 'Alan Sturdy' to 'Alan Brady', and created a five year hit known as The Dick Van Dyke Show.
Heat Vision and Jack: 1999 comedy/sci-fi show starring Jack Black as Jack Austin, a former astronaut exposed to inappropriate levels of solar radiation, granting him super-intelligence whenever the sun is out. Since NASA wishes to take out his brain, he's on the run with his friend Heat Vision, a friend who has been hit by a laser beam and turned into a talking motorcycle (Voiced by Owen Wilson). They travel the countryside chased by NASA mercenary Ron Silver (as himself), blocked at every turn...by adventure! Directed by Ben Stiller.
- Created by Dan Harmon who gave the leads (Black and Wilson) a guest appearance on a show of his that did get picked up.
Heil Honey I'm Home: A 1990 British comedy starring caricatures of Adolf Hitler and Eva Braun who live in matrimonial bliss until they become neighbors to a Jewish couple... Let's just say it's no Hogan's Heroes.
K-9 and Company: Doctor Who spinoff. Aired as a Christmas special in 1981 and starred former Doctor Who regular Elisabeth Sladen as Sarah Jane Smith, the pilot featured a silly plot involving a local coven. It probably would've gone to series at the time, but then-recently appointed BBC One controller Alan Hart opposed the concept. 26 years later, Sarah Jane returned in her own spinoff series, The Sarah Jane Adventures, which fared much better.
Korgoth of Barbaria: 2006 animated pilot for a ridiculously over-the-top parody of Conan the Barbarian and other such barbarian fantasy novels/movies, created by Aaron Springer. Originally said to have been picked up by the Adult Swim lineup in 2007, but later said to be canceled with nary an episode other than the pilot.
Lawless: 1997 FOX action series starring NFL star Brian Bosworth as a private detective.
Locke and Key had a pilot filmed in 2011 for Fox, but it wasn't picked up to series.
Lookwell: 1991 detective comedy series written and produced by Conan O'Brien and Robert Smigel. Stars Adam West as a washed-up TV action star who, after being legally deputized at the peak of his career, decides to fight crime, which he does ineptly. The two writers were reportedly happy they didn't get picked up, feeling they had exhausted all good material on the pilot and no idea what to do for further stories.
Lost in Oz: 2002 series sequel to The Wizard of Oz, written by David Hayter, screenwriter of the first two X-Men films and voice actor of Solid Snake.
The Melting Pot: 1975 BBC production. Two stereotyped illegal-immigrants from Pakistan arrive in England via Amsterdam and move into lodgings run by an stereotyped Irishman. Hilarity Ensues.
Jennifer Saunders re-assembled the main cast of Absolutely Fabulous to play different characters in Mirrorball. The classic slapstick and the satire were all there, but Saunders traded in her Rich Bitch Unsympathetic Comedy Protagonist and her Rich in Dollars, Poor In Sense friends, for a Giftedly Bad down-on-her-luck actress and her more sympathetic band of Starving Artists. It didn't catch on.
The Modifyers. The pilot can be found here.
MTV Ultimate Mash-Ups: Originally intended to be a series bringing artists together for collaborations, the first mash-up, between Jay-Z and Linkin Park, was a huge success, yet MTV never created another one. Ludacris and Sum 41 were rumored to be the next collab at one point.
The Naked Brothers Band animated special Supetastic 6.
Out Of The Trees, a 1975 stream-of-conciousness sketch show written by Graham Chapman and Douglas Adams. One episode was made, and was put out on BBC2, with no publicity, opposite Match of the Day on BBC 1. It included "The Private Life of Genghis Khan", which eventually got rewritten as a short story for The Utterly Merry Comic Relief Book, and reached a wider audience in The Salmon of Doubt, and a sketch about a kamikaze pilot who had flown on dozens of missions, which was interrupted while the narrator tried to get some Japanese background music.
Pauly Shore has a habit of pumping these sort of shows out. His first series, simply titled Pauly, was actually canceled halfway through the airing with only five episodes produced, with the footage replaced by an apology from the network.
Pryde of the X-Men: Surreal 1989 Kitty Pryde-based animated X-Men adaptation, which laid the ground work for the later series, after a much needed retool. Stan Lee's hyperactive narration takes it to the next level. The inclusion of Dazzler in the main cast and the fact that the historically Canadian Wolverine has an Australian accent probably didn't help either.
- Nowadays, most fans would recognize the show's character designs as those used in the popular X-Men Beat'Em Up arcade game.
The American version of Red Dwarf didn't survive past a single pilot episode that never made it to air. Notable for casting Terry Farrell (of Star Trek: Deep Space Nine fame) as a female version of Cat, a pre-Frasier Jane Leeves as the computer Holly and Robert Llewellyn reprising his role of Kryten from the original British series. Because of Executive Meddling late in the production, multiple actor recastings and other problems, British series footage had to be used to fill in the holes in the episode. A brand-new higher-quality Kryten suit was made for the pilot which Llewellyn was allowed to keep and re-use in further British seasons following the American cancellation.
The Robinsons: A 2003 Lost In Space remake pilot commissioned by the WB Television Network. The pilot was directed by John Woo (of Hard-Boiled and Face-Off fame), and featured multiple changes from the original, such as: the Jupiter 2 being a landing pod instead of a full-fledged ship, one of the Robinsons' sons dying in an attack by aliens, and much younger actors playing Judy and Don Robinson. The show was never picked up, but the sets of the Jupiter 2 were bought for use on the re-imagined Battlestar Galactica, as the Battlestar Pegasus' command center.
Ronna and Beverly: 2009 Showtime sitcom based on a live sketch comedy show about two middle aged Jewish women who write a bestselling self-help book. The pilot was written by Jenji Kohan, whom you might know better as the creator of Weeds. When the pilot wasn't picked up, fans of the duo petitioned Showtime to air it, which they did in the dead of a cold December night.
- This isn't the only Jenji Kohan series to have never gone past the pilot stage. One year later, Epix decided to pass on picking up her pilot Tough Trade due to budget and the company not liking the pilot. It has yet to be leaked.
Rosie Live: O'Donnell's 2008 attempt to revive the Variety Show format.
Secret Talents of the Stars: Hosted by John O'Hurley, it had George Takei singing country. You just can't say anything more than that.
- Actually, you can. Mya billed her secret talent as tap dancing. Anyone seen My Love Is Like... Wo?
McG's American version of Spaced had a pilot filmed, but it never got picked up.
Sucker Free City, a 2004 Pilot Movie by Spike Lee aired on Showtime.
Superboy 1961: A planned prequel series (or possible reboot) to the George Reeves series, The Adventures of Superman, the pilot followed a young Clark Kent as he attempts to thwart a gang of jewel thieves.
Tag Team: Jessie Ventura and "Rowdy" Roddy Piper play wrestlers drummed out of the business for refusing to take a dive. They then go on to become police officers. They Fight Crime.
Turn-On: 1969 ripoff of Rowan and Martins Laugh In with nonsensical jokes, including people making funny faces while the word "sex" pops up. One of the most notorious flops in ABC's history, the Denver and Cleveland affiliates failed to return to the show after the first commercial break, replacing it with a documentary on pistol shooting. Due to being profiled in seminal works like the original The Book of Lists, Turn-On is arguably the most famous/infamous example of a One Episode Wonder.
The TV Wheel: 1995 experimental sketch-comedy show created by and starring Mystery Science Theater 3000's Joel Hodgson. Heavy on the "experimental", but worth a look. It was originally developed for HBO and known as "The X-Box"... No relation.
Virtuality, which aired on FOX. Originally intended as a pilot, but canned preemptively.
W*A*L*T*E*R, a spin-off of M*A*S*H focusing on Radar O'Reilly's return to civilian life in Iowa. Its one episode actually reached the air as a special on July 17, 1984, making it possible for a copy to [exist on YouTube for the curious.
Welcome to Eltingville, an animated adaptation of Evan Dorkin's comic book Dork! about a group of fanboys on Staten Island. Adult Swim occasionally re-airs the pilot along with other Wonders. Presumably to taunt us.
Which Way to the War?, an ITV sitcom (with all that implies) pilot clearly intended for a full series which was broadcast in the 1990s. It featured a range of stereotypical WWII soldiers of various nationalities (the trailer showed a camp Scotsman saying "I'm not Scotch. I'm Scottish", this apparently being the joke they hoped would reel in interested viewers) along with 1970s-style writing and production values. Never heard from again.
Who's Your Daddy: 2005 FOX reality show involving an adopted woman attempting to pick her real father from a group of impostors. The Raleigh affiliate, WRAZ, pre-empted the show due to the owners considering the show "anti-family". Technically aired as a "special", but was so quite clearly a pilot that it's worth mentioning.
The Will: 2005 CBS reality show. It centered on the "Benefactor", a multi-millionaire from Arizona named Bill Long. Ten of his friends and relatives competed in a series of challenges to win the right to inherit his "prized possession", a huge Kansas ranch. The series eventually aired in its entirety on FOX Reality Channel.
You're in the Picture: 1961 CBS game show hosted by Jackie Gleason where the celebrity panel put their heads in cut-outs of painting reproductions,and had to guess the scene depicted. It was slaughtered by critics so much that in its timeslot the following week was Gleason delivering a hilarious ranting apology for the previous week's show (which wound up leading into Gleason's famous talk show The Jackie Gleason Show). Gleason's half-hour apology is considered one of the premier mea culpas of the television age.
NBC's 2011 Wonder Woman series, which was quietly canned after receiving massively negative feedback from test audiences. The incomplete pilot was eventually leaked onto the Internet, which allowed fans to see precisely why it was savaged: Wonder Woman is a violent vigilante who thumbs her nose at the law and tortures a crook for information so she can slander Liz Hurley—in other words, not Wonder Woman at all.

Two-Episode Wonders

In general, many OVAs produced during the 1990s anime boom wound up as this. Amusingly enough, a good number of them were licensed in the west by ADV Films and/or Media Blasters, most of which are considered cult classics by people who got into anime at that time.
- Even more amusingly, the Fire Emblem OVA, which fits this trope perfectly, made it to the west before the games did!
The Adventures of Kotetsu.
Apple Pie, an eccentric 1978 sitcom starring Rue McClanahan and Dabney Coleman, created by Norman Lear. Seven episodes were produced, but ABC only aired two of them.
Ayane-chan High Kick! (aka Ayanes High Kick): A female Ordinary High School Student with dreams of getting into Professional Wrestling is scouted by a former kickboxer who tricks her into getting into the sport because of her incredibly-powerful kicks.
Clerks the Animated Series. Although six episodes were produced, only two were shown on the network that commissioned the show.
Dragon Half. Legend has it the OAVs were cancelled after the mangaka was busted for drug possession.
The softcore Hentai anime Elf no Waku Okusan (aka The Elven Bride), detailing the attempts of a human and his wife, an elf to consummate their marriage despite the titular bride's incredibly small...er, "receptor".
Elf Princess Rane only lasted two episodes before the creators "ran out of budget". This is highlighted by a close-up of one of the characters begging the viewing audience for more money so they can continue the series.
Girls Club, a 2002 David E. Kelley-created show about a trio of young female lawyers, had six episodes produced but only two aired.
ABC dumped The Great American Dream, a modern equivalent of Queen for a Day in which female contestants got to see their dreams come true. It was hosted by Donny Osmond. Five episodes were taped, but only two aired.
Hardwicke House, a 1987 British Alternative Comedy sitcom about an anarchic school, was ill-advisedly scheduled in ITV primetime. A media campaign led to its cancellation after two episodes. It was not repeated, and now nobody is even sure if tapes of the other five episodes still exist.
The Henry and June Show, a spin-off of KaBlam!.
FOX drama Lone Star is a bit of an odd example because it was supposed to be the network's big show for 2010; however, it was canned after two episodes due to abysmal ratings.
Mighty Space Miners
And yet another FOX example: the 2007 reality series Nashville, which featured up and coming country music stars, including Jamey Johnson, Chuck Wicks (later a Dancing With the Stars finalist) and Terry Bradshaw's daughter Rachel. Six taped, two aired.
The Paul Reiser Show aired on NBC in 2011 for two weeks, then was cancelled due to very poor ratings. NBC was not doing very well at the time, so the show had to have been doing pretty poorly to be cancelled so quickly.
ABC Disguised in Drag comedy Work It! was cancelled after two episodes due to low ratings and protests from the GLBT community.
Puni Puni Poemi
The Roaring Twenties.
The Sonic the Hedgehog OVA had only two episodes (see the note at the top of this section).
Special Duty Combat Unit Shinesman, based on a 9-volume manga series.
Viva Laughlin.
Penny Arcade Adventures: Four episodes were planned. Only two were made.
Another episodic game example: Telltale Games' Bone. We can assume they were going to go through all 9 chapters of the series, but they only got to the second chapter, "The Great Cow Race", and then dropped it. Although it's still available to purchase from their site, and nothing has said they'll never come back to it...
Hank Azaria's attempt to get a career beyond The Simpsons, Imagine That, was cancelled after two episodes aired.

Not actually an example

In May 2004, PAX debuted a Game Show called On The Cover, which aired for two episodes before abruptly stopping. It came back later in the year with some (mostly cosmetic) changes, but was gone again after its first "real" season.
And subverted again with another game show, The Rich List. One of countless one-episode wonders from FOX (2006 in this case), it was Re Tooled two-and-a-half years later as The Money List, which aired on GSN...for nine episodes.
G4's Proving Ground, an Experiment Show focusing on recreating things from video games, movies, and TV shows, was pulled off G4's schedule after co-host Ryan Dunn died in a car accident after only one episode had aired. The remaining eight episodes were eventually quietly run off later in the summer. No statement has been made on the show's continuation with a new co-host.
An interesting case involves The Miraculous Year, an HBO pilot written by John Logan and directed by Kathryn Bigelow (her first directing job after winning an Academy Award) and featuring an All-Star Cast including Frank Langella, Susan Sarandon, Lee Pace, Hope Davis, Linus Roache, and Eddie Redmayne about the dysfunctions of a family of people who work in and around Broadway. Despite the pedigree of the cast and crew, the project was dropped by HBO before the pilot even aired, allegedly because the network was worried it was an Audience-Alienating Premise.
There have also been cases of shows cancelled after one or two episodes going on to longer runs elsewhere. An example being the aforementioned series The Will, which was cancelled almost immediately by its host network, but later played in full on a cable channel.

In-universe One-Episode Wonders and Parodies

Class Holes!: An in-universe sitcom in Family Guy created by Brian Griffin after CBS rewrites the script starring James Woods attending college with his daughter. It only aired one episode due to very low ratings. The script was intended to be a drama called What I learned on Jefferson Street which is about a single father played by Elijah Wood returning to college to give him and his 4-year-old daughter a better life.
- Also in-universe, Peter had a show he made called "Handiquacks", the first episode aired when the CEO wanted to make a very, very minor change to one of the characters, Peter said no and left, then wound up kicking himself later when he realizes his idiotic pride just prevented him from getting several thousand dollars.
The Dana Carvey Show: Had a fake newscast during the end credits of its premiere declaring that it had been canceled 15 minutes into its first episode. It did get a few more episodes than that...
Futurella, the new sci-fi animated show that Matt Groening's head shows a teaser trailer of to the 3010 Comicon audience in Futurama...and which FOX cancels three seconds in, prompting Groening to admit that the process has been streamlined.
Jerry: In-universe TV show that Jerry Seinfeld and George Costanza were continually trying to make. Lasted only one episode, in part because the only executive on their side ran away to join Greenpeace for all the wrong reasons. They very nearly got it on the air, but then they were thrown in jail.
Limozeen: But They're In Space!: Animated television series in the Homestar Runner universe (and according to Strong Bad, the greatest thing he's ever "seen, done, or eaten") starring the Fake Band Limozeen and their fantastic adventures in space. The show was canceled during the airing of its pilot, and the characters themselves halt the episode halfway through to inform the viewers to watch their future adventures in syndication or on DVD. The "end credits photo montage" of the email "Montage" mentions that "Strong Bad went on to host some show on Animal Planet. It was canceled before the first commercial break."
Seein' Double: a show created within Newhart by aspiring TV producer Michael, starring Stephanie as identical twin sisters and Dick as their father. Basically The Patty Duke Show meets Three's Company, with a whole lot of Stylistic Suck in both the acting and the writing.
White Rice in American Dad gets cancelled after one joke, probably setting a record for both real and fake shows.
Wormhole X-Treme, the Show Within a Show in Stargate SG-1 was variously said to have only run one episode before being cancelled ("Citizen Joe") or three episodes ("200") and got a feature film because it performed well on DVD.