History Retool / LiveActionTV

* ''Best Ever Trivia Show'' debuted on GSN in June 2019. Three contestants and three house experts would answer trivia questions; contestants would win more points if a selected expert failed to get the question right. The contestant who won would face the best performing expert for the chance to win $10,000 and the right to return and play again; three bonus round victories meant the contestant would become an expert themselves. The second season debuted in April 2020, keeping the core premise and theme song, but changing everything else. The title was switched to ''Master Minds'' (which is also what the experts themselves were now called), host Sherri Shepherd was replaced by Brooke Burns, and the set's rainbow motif was jettisoned in favor of painting everything blue. The main game took on a more head-to-head bent and added a speed round, while the bonus round had the day's champion and Master Mind answer their five open-ended questions separately, as opposed to the first season's method of having them answer five multiple-choice questions simultaneously.

* ''The Doris Day Show'' changed formats almost every of the five seasons it was on air. Originally it was about the eponymous star as a widowed mother of two sons who decided to move back to the family ranch. In season 2, she took a job at a San Francisco magazine and commuted to work. A year later the family moved to an apartment in the city while Day's character went from a secretary to a reporter. For the last two seasons the show was completely overhauled; the two sons and most of the supporting cast (which had changed every year up to that point) were dropped without explanation, Doris became a swinging single career woman a la Mary Tyler Moore and she was referred to as always having been a reporter. The only thing that remained constant about the show during its five-year run was its lead actress.

* One of the most infamous examples was ''Series/BaywatchNights''. This ''Series/{{Baywatch}}'' spinoff involved the show's resident police officer, Sgt. Garner Ellerbee (Gregory Alan Williams) decide to open a detective agency, being joined by Mitch Buchannon (Creator/DavidHasselhoff) and Ryan [=McBride=] (Creator/AngieHarmon) and have them deal with street crime. Then when the show proved to be a flop, the producers were inspired by the success of ''Series/TheXFiles'' and decided to replace Ellerbee (who, again, ''founded the agency'') with a paranormal investigator and turn the show into "David Hasselhoff fights aliens, mutants and ghosts".

* ''Series/SuddenlySusan'' was a comedy about a career-minded woman who works as a writer with a local newspaper. During the jump from the third to fourth seasons, several characters disappeared (including Susan's boss, who she had previously admitted being in love with, and a newspaper employee [which was caused by the actor who played him killing himself]), the introduction of a new boss and an overhauled office setting. This retool wasn't really motivated by ratings either, as they had stayed relatively consistent. However, the show was cancelled soon afterwards.

* ''Series/SonnyWithAChance'' is about small town girl Sonny who joins the cast of her favorite sketch comedy show ''[[ShowWithinAShow So Random!]]''. Music/DemiLovato (who played the titular character) ended up quitting the show and taking a temporary break from acting after season two, to deal with some personal problems and also focus on her music career. Disney retooled it by {{defictionaliz|ation}}ing ''Series/SoRandom''. Yep, the show within the show became the actual show!

* In its second season to accommodate its full-time move to Nick Jr. (probably due to ExecutiveMeddling), ''Series/TheWubbulousWorldOfDrSeuss'' abandoned its half-hour story, replaced the Cat's voice with a less gravelly alternative, and became more of a ''WesternAnimation/BluesClues''-style kids show. [[TheyChangedItNowItSucks Season 1 is viewed as superior]].

** Season 1 of ''Series/StarTrekDiscovery'' was about a war between TheFederation and the Klingon Empire (along with a brief jaunt into the MirrorUniverse). Once that wrapped up, season 2 focused on an investigation of a series of strange phenomena which turned out to be connected to a threat from within Starfleet. As the season ended with [[spoiler:USS ''Discovery'' being thrown over 900 years into the future]], we're in for an even more radical retooling in season 3.

* CBS' primetime drama ''Series/CentralParkWest'' suffered this. The show was originally about a pair of siblings who immersed themselves in the world of high-class socialites, and got caught up in all the backroom deals and intrigue that followed. In the second season, the theme song was changed (from a sultry and mysterious jazzy song to the type of theme you'd hear on a cheesy soap opera), the show was marketed as "CPW", half the cast was jettisoned (including one of the two siblings), Raquel Welch was cast as an [[Series/{{Dynasty}} Alexis Carrington-esque]] business owner, and many story arcs were dropped. However, it could be said that the show immediately improved as a result of this retool (especially since the writers dropped the pretenses and started having fun with the material). Then, it was cancelled shortly thereafter.

* ''Series/InTheHouse'' starred Music/LLCoolJ as retired football player Marion Hill. Facing financial straits, he rents out the extra three bedrooms of his Los Angeles mansion to newly-divorced mother Jackie and her two children: teenage Tiffany and preteen Austin. The show initially dealt with Marion adjusting to life after football, Jackie re-entering the workforce and dating scene, and the kids' hijinks. After two seasons and a ChannelHop, the series was retooled to focus on the 18-34 demographic: Jackie and Austin [[PutOnABus move away]] while Tiffany stays in LA with Marion to attend college, and Marion buys a sports clinic where he's joined by Max and Tonia to help run it. Eventually even Tiffany is written out to focus more on the clinic and the adult trio's love lives.

* The original ''Series/{{MANTIS}}'' took place in Ocean City and dealt with race issues, including the backstory for the title character, Miles Hawkins, involving getting shot and paralyzed in the LA Riots (which inspired the creation of the exosuit he uses to fight crime). In the series proper, the setting is Port Columbia with the only hold over of the race issues being Miles's backstory. Midway through, the series was retooled again and fully embraced being a superhero show, including other universes, supervillains, and time travel.

* The 2007 ''Series/{{Flash Gordon|2007}}'' remake was retooled during a mid-season hiatus to combat highly negative fan reactions. The MonsterOfTheWeek format was abandoned in favor of an arc-based storyline, Flash's BlackBestFriend was dropped from the cast and much more screen time was spent on Mongo in general. It didn't save the show from being canceled, although many fans thought it got better after the retool.

* After "Series/MysteryScienceTheater3000'' moved to the [[Creator/{{Syfy}} Sci-Fi Channel]] with their eighth season (and actor Trace Beaulieu, who played Dr. Forrester and Crow) left, they got new villains, a new setting, and (due to ExecutiveMeddling) an actual ongoing plot. At the end of the season, some of these changes were backed off on, with a move to a setting similar to the first seven seasons and a lack of stories that carried on between episodes (though the 10th season had a subplot that was dropped halfway through).

* ''Series/TheAvengers'' was originally about Dr. David Keel (played by Creator/IanHendry) teaming with a mysterious secret agent named John Steed and their investigation into crimes. In the second season Hendry left and Steed became the lead. Steed then gained a new partner, the leather-clad, judo-knowing Cathy Gale, the first ActionGirl of many that Steed would be partnered with through the decade. After her would be the most famous to American audiences, Emma Peel and finally Tara King.

* In its second season to accommodate its full-time move to Nick Jr., ''Series/TheWubbulousWorldOfDrSeuss'' abandoned its half-hour story, replaced the Cat's voice with a less gravelly alternative, ditched the CGI backgrounds and became more of a ''WesternAnimation/BluesClues''-style kids show.

* ''Series/BarneyAndFriends''' format has constantly changed. Season 4 introduced a fully redesigned school set. Season 7 moved the setting from a school to a park. Season 9 mixed park segments with parts on a white background featuring just the dinos. Season 10 introduced Riff and took on a TwoShorts format. Season 12 reverted to the full-length format and focused on story genres. Season 13 was about countries and cultures.

* ''77 Sunset Strip'' got one of these for its sixth and final season, with the entire cast save for Efram Zimbalist Jr. replaced, Zimbalist's character given an entirely different history and personality, and the show's overall tone getting much darker and more FilmNoir-ish. Viewers largely [[TheyChangedItNowItSucks hated the changes]] and stayed away in droves, leading to the show's abrupt cancellation midway through the season.

* One of the most infamous examples was ''Baywatch Nights''. This ''Series/{{Baywatch}}'' spinoff involved the show's resident police officer, Sgt. Garner Ellerbee (Gregory Alan Williams) decide to open a detective agency, being joined by Mitch Buchannon (Creator/DavidHasselhoff) and Ryan [=McBride=] (Creator/AngieHarmon) and have them deal with street crime. Then when the show proved to be a flop, the producers were inspired by the success of ''Series/TheXFiles'' and decided to replace Ellerbee (who, again, ''founded the agency'') with a paranormal investigator and turn the show into "David Hasselhoff fights aliens, mutants and ghosts".

* Bob Newhart's third series ''Bob!'' was the story of Bob [=McKay=], a greeting card artist who had a few decades earlier created a semi-successful comic book character called "Mad Dog". When Ace Comics offers him a chance to revive the book he quits the greeting card company and deals with the wacky people who work for the comic book company. After the first season the series was renewed, but in the first episode of the second season it is explained that Ace Comics went out of business and Bob crawled back to the greeting card company to get his job back there (and deal with the wacky people there). This version only lasted a few episodes before it was canceled.

* ''Series/TheBill'' has undergone several in its 26+ year lifespan. The most dramatic were in 2002 (when 7 of the regular long standing cast members were killed off in a single episode), and 2009 (when the series moved to HD, started being broadcast after {{Watershed}}, and completely replaced its theme music with a different tune for the first time ever).

** Lampshaded in the first episode of its fifth season; most of the study group have left Greendale, but have generally been unsuccessful in their new careers or found them unfulfilling, forcing them back to the college for more study. Abed lampshades the fact that bringing the group back together for more shenanigans around Greendale is akin to a retool, explicitly referencing the ninth season of ''Series/{{Scrubs}}''. Not surprisingly - considering the show's penchant for meta and self-awareness - this season sees some of the biggest changes in the format of the show; two of the seven main cast members leave (one of whom is replaced by a surprisingly ''not'' SuspiciouslySimilarSubstitute {{Expy}}), a season one recurring character who had a case of ChuckCunninghamSyndrome returns, and Chang is finally (if reluctantly) accepted as a regular member of the study group.

* ''Series/{{Nikita}}'' flips it status quo around in season 3 as a result of the events of the second-season finale. [[spoiler:In light of [[BigBad Percy's]] death, Division is taken over by the government and Team Nikita, who start using its resources to hunt down the remaining Division agents who don't join in the HeelFaceTurn]].

* Famed sitcom ''Series/{{Rhoda}}'' was retooled at least twice during it's four year run. First, Rhoda and her husband Joe separated and she got a new job. Then, she and Joe got divorced and [[ChuckCunninghamSyndrome he disappeared from the show]], then she got yet another new job, and her parents separated as well.

* In the 9th season of ''Series/{{Scrubs}}'', the series moves from Sacred Heart Hospital to a medical school and the focus characters become the new students.

* ''Series/{{Space1999}}'' : Season 1 was rather thoughtful and existential with an atmosphere of both genuine danger and epic grandeur and could almost have been shot in black and white. It featured a huge, multi-level main set, awesome space battles, and a sweeping orchestral score. Season 2 was far more simplistic, fast-moving and colourful, with loads more monsters, comedy robots and running around. Several main characters were ditched without explanation, a shape-shifting alien hottie was introduced, there was more focus on the characters personal relationships, the sets were smaller and more intimate and the score was largely replaced by funky guitar. Even the heroes uniforms were changed, with jackets, mission patches and ID badges added for extra colour and interest.

*** The third season dropped Pulaski and brought back Dr. Crusher, but it was also defined by the new uniforms that were more comfortable for the actors (being two pieces instead of jump suits) and had a more professional look to them having high collars, instead of the goofy looking space pajamas of prior seasons.

* ''Series/TopGear'' originally ran from 1977 until 2001, when it was cancelled. Although it relaunched just a year later in 2002, "new" Top Gear is fundamentally different in spirit and character to its predecessor. The original was an informative/factual news and review magazine about cars, and though it became far less dry and more entertaining in the way it did this as time went on, at heart it remained true to that. While the relaunched format isn't uninformative (and does overlap the original in places), it's clear that its ultimate focus is to entertain the viewer, with everything in the end serving that purpose. Unlike the original, it's far more studio based, and more focused on the characters and interplay of the presenters- often intentionally played-up- with the cars often being a means to that end, rather than the point in themselves. Much of the show essentially lets the viewer participate (by proxy) in what James May himself called "self-indulgent cocking-about".

* ''Series/{{Unforgettable}}'' was canceled after its first season, then UnCanceled a year later because a couple cable channels were eyeballing it. As a result season two has completely new sets, swapped out most of the supporting cast (though they kept the coroner), and the season premiere ignored the MythArc (though we'll see if the last part stays the case).

* ''Series/KirbyBuckets'', during its first two seasons, was a sitcom about a teenage boy who wanted to be a professional cartoonist, not unlike ''Series/OutOfJimmysHead''. The format then shifted in season 3 to become a dimension-warping action show. The cartoon cutaways were dropped, and the episodic format was replaced by a serial-style series.

* To say that the second season of the 1980s ''Series/WarOfTheWorlds'' TV series used some "[[ExecutiveMeddling creative liberties]]" would be stating it lightly. In the jump between seasons, the plots become ''much'' more DarkerAndEdgier, and the the entire style of the show changed from a somewhat lighthearted, highly cerebral communism metaphor into a dystopian near-future proto-cyberpunk survivalist fantasy (handwaved at the beginning of the second-season premiere by an alien hand gripping Earth and causing darkness). Half the cast either disappeared (General Wilson) or were killed off (Colonel Ironhorse, Norton Drake), the main antagonists of the first season were unceremoniously executed, a new group of aliens took their place as the villains and the setting changed from a mansion to a ''sewer base''. The fans were not pleased.

* ''Series/ThaMagician'': Midway through the program's run, the idea of Tony living on an airplane was dropped and Blake took up residence in a posh apartment at The Magic Castle, a real club devoted to magic acts. At the same time, the supporting cast of the show was replaced with a new, single character, Dominick (Joseph Sirola), a somewhat comical sidekick. No explanation for the changes was given in the series.

* The original ''Series/{{MANTIS}}'' took place in Ocean City and dealt with race issues, including the backstory for the title character, Miles Hawkins, involving getting shot and paralyzed in the LA Riots (which inspired the creation of the exosuit he uses to fight crime). In the series proper, the setting is Port Columbia with the only hold over of the race issues being Miles's backstory. Midway through, the series was retooled again and fully embraced being a superhero show, including other universes, supervillains, and time travel.
* The first three seasons of ''Series/{{MASH}}'' were primarily a wacky ArmedFarces comedy, focusing on "antics at the front". With the departure of main characters Trapper John [=McIntyre=] and Henry Blake (the latter via a shocking [[BusCrash offscreen death]] in the Season 3 finale), and the arrival of [[ShooOutTheClowns much more serious]] replacements [=B.J.=] Hunnicutt and Sherman Potter, the show transformed into a {{Dramedy}} series, with most episodes dealing with serious issues such as racism, homophobia, sexism, and of course, the horrors of war. The show's LaughTrack was also toned down, and even dropped altogether for some episodes.

* The 2018 revival of ''Series/{{Roseanne}}'' was retooled into ''Series/TheConners'' after one season, with Roseanne herself being McLeaned after Creator/RoseanneBarr made controversial remarks on social media.