History Retool / LiveActionTV

* 90s NBC sitcom ''Jesse'' (starring Christina Applegate) was, quite typical for its era, about a single woman in her twenties with a major WillTheyOrWontThey plot, but distinguished itself somewhat by originally featuring the main character's family (wacky brothers and gruff father) in major roles, as all of them worked at the dad's bar together. However, that family [[ChuckCunninghamSyndrome vanished]] in the second season as Jesse got a new job at a hospital with young and attractive colleagues, while her girlfriends got more screentime than in the first season. The producers were obviously trying to make the show more similar to [[Series/{{Friends}} a certain other show of theirs]].

* ''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 (and the theme song).
* The 80s teen sitcom ''Double Trouble,'' starring twins Jean and Liz Sagal (sisters of Katy), revolved around their life in Des Moines, Iowa, being raised by a single dad (Donnelly Rhodes) who ran a dance studio. The second season did a major retool and sent them to New York City, where one sister tried to make it as a dancer and the other attended fashion school with a tactless, snarky professor. They lived in a townhouse with their eccentric aunt and two kooky single guys. (There was no third season.)

* Bob Newhart's third series ''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/MamasFamily'', like ''Charles in Charge'', got retooled when it moved to syndication and replaced two thirds of the family - Vicki Lawrence as Mama, Ken Berry as her son Vinton and Dorothy Lyman as Vinton's wife Naomi stayed; Vinton's son and daughter, Thelma's sister Fran and older children Ellen and Eunice, and Eunice's husband, were all written out and replaced by Eunice's son Bubba and the family's neighbor Iola Boylen.

* ''The Lenny Henry Show'' (staring British comedian Creator/LennyHenry) ran from 1984-1985 as a sketch show featuring a variety of different characters played by Lenny Henry. It returned in 1987 under the same name, but this time as a sitcom around the character Delbert Wilkins.

** The very first season had its lead actor, Hiroshi Fujioka, involved in an accident, which made it impossible for him to continue involved in the show's production for an extended period. Initially, that led to a ''FakeShemp'' Hongo, who mostly appeared as Kamen Rider, played by a replacement suit actor and voice actor, and also through StockFootage spliced with new scenes. In spite of that, the focus shifted to the supporting cast, and FBI agent Kazuya Taki was introduced as a non-super powered heroic lead. After a few episodes, a new protagonist and Kamen Rider, Hayato Ichimonji, was added, Hongo Takeshi left to fight against Shocker in other countries, and the show went through several changes, like lessening the horror elements of the first few episodes and the creation of the instant transformation sequence with a "henshin" call that would go on to become one of the franchise's trademarks. Ruriko, Hongo's love interest, was phased out of the series, the hangout spot of the supporting cast was changed and three new girls were introduced alongside Hayato. The soldiers working for the organization Shocker also started sporting a more uniform look with wrestling masks, rather than the varied situation appropriated look from the first 13 episodes. The changes were a success and the series exploded in popularity. Eventually, Hiroshi Fujioka recovered and returned to the series as Hongo, recovering the main character spot after a few months of guest appearances, but, even when he returned, the style of the series didn't shift to its initial one.

** Jadzia Dax and Julian Bashir were given a soft reboot as characters during Season 2. In the first season, Jadzia was a serene "old soul" in the body of a young woman who seemed above the passions of people younger than a century. The premiere of the second season retains her confidence but she also engages in quips and gossip with her colleagues. "Playing God" establishes her as lively and fun-loving. Julian's character is refocused from "hapless flirt and InsufferableGenius" to DeterminedDoctor. Like Dax, this crystallizes in one episode, "The Wire," where the lengths he goes to save a former black ops agent provides the page quote for that trope.
** The series brought in Worf in the fourth season and redirected the story towards a new Klingon conflict. While it was due to ExecutiveMeddling, it was considered a successful integration and helped further their Dominion StoryArc by revealing the Klingons were being manipulated by them. The end of season 5 retooled the show again by starting the inevitable war between the Federation and the Dominion, thus setting the tone for the last two seasons.

** ''Series/StarTrekDeepSpaceNine'' brought in Worf in the fourth season and redirected the story towards a new Klingon conflict. While it was due to ExecutiveMeddling, it was considered a successful integration and helped further their Dominion StoryArc by revealing the Klingons were being manipulated by them. The end of season 5 retooled the show again by starting the inevitable war between the Federation and the Dominion, thus setting the tone for the last two seasons.

* ''[[Series/Cursed2000 Cursed (2000)'' was a sitcom starring Creator/StevenWeber as a man [[ExactlyWhatItSaysOnTheTin cursed]] by his ex-girlfriend and his unending stream of bad luck. This somewhat one-note premise having a limited appeal, it was renamed ''The Weber Show'' and retooled as a kind of gender-reversed ''Series/WillAndGrace'' focused on Weber's friendship with a LipstickLesbian. The show still only lasted one season.

* ''Series/Cursed2000'' was a sitcom starring Creator/StevenWeber as a man [[ExactlyWhatItSaysOnTheTin cursed]] by his ex-girlfriend and his unending stream of bad luck. This somewhat one-note premise having a limited appeal, it was renamed ''The Weber Show'' and retooled as a kind of gender-reversed ''Series/WillAndGrace'' focused on Weber's friendship with a LipstickLesbian. The show still only lasted one season.

* ''Cursed'' was a sitcom starring Creator/StevenWeber as a man [[ExactlyWhatItSaysOnTheTin cursed]] by his ex-girlfriend and his unending stream of bad luck. This somewhat one-note premise having a limited appeal, it was renamed ''The Weber Show'' and retooled as a kind of gender-reversed ''Series/WillAndGrace'' focused on Weber's friendship with a LipstickLesbian. The show still only lasted one season.

* ''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 ''Series/MasterMinds'' (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. Still later, the bonus round switched to them answering the questions simultaneously, writing their answers down.

* Inbetween a three-year hiatus, ''Brain Games'' transformed from a reality show where random people from off the street played said games into a game show with celebrity guests, with its host Jason Silva being replaced by the more-famous Creator/KeeganMichaelKey.

* The Creator/ChannelFive soap ''Family Affairs'' had several retools. The first one [[ArtifactTitle got rid of the eponymous family entirely]], and later ones were even more drastic. None of them seemed to help the ratings, though.