Gunsmoke, Cheers, M*A*S*H and Happy Days are some of the longest-running primetime series in television history. When a show lasts for a decade, audiences clearly care. 

No wonder that networks then try to keep a good thing going with spin-offs. Happy Days spawned Laverne & Shirley, which went on to become the most-watched show on television in 1977. Cheers begat Frasier, which lasted just as long as its parent, 11 seasons.

But those juggernauts also gave us Blanksky's Beauties and The Tortellis. They can't all be winners.

The following 10 shows were all born from beloved classics — and they all flopped. Did you watch any of them?

1

Blansky's Beauties

Happy Days
13 episodes

Garry Marshall became somewhat obsessed with making a sitcom about Las Vegas showgirls. His first attempt was built as a spin-off of his smash hit Happy Days. Laverne & Shirley and Mork & Mindy, which premiered in the autumns of 1976 and 1978, respectively, were both wildly successful spin-offs of Happy Days. However, there was another spin-off between those two pop-culture sensations. On February 4, 1977, Happy Days aired its "Third Anniversary Show" episode. Nancy Walker guest-starred as Howard Cunningham's cousin Nancy Blansky, a Las Vegas showbiz professional who acted as a den mother to a gaggle of showgirls. This led to a full series titled Blanksy's Beauties, which began the following week on ABC. The cast of Beauties also included the young and lovely Lynda Goodfriend as "Sunshine," as well as 16-year-old Scott Baio, who played a precocious and tough 12-year-old named Anthony DeLuca. The show also had a link to Laverne & Shirley, as Eddie Mekka, the actor best known as Shirley's boyfriend Carmine Ragusa, portrayed the character Joey DeLuca, the Carmine's younger cousin

Image: The Everett Collection

2

Dirty Sally

Gunsmoke
13 episodes

Dirty Sally holds the distinction of being the only spin-off of Gunsmoke in the show's 20-year run. Perhaps they shouldn't have waited so long. This series began as the two-part finale of season 16, "Pike," in which a young gunslinger named Cyrus Pike (Dack Rambo) is nursed back to health by a toothless outcast named Sally. Sally, a sort of cross of Yosemite Sam and a crusty old witch, was played by the venerable Jeanette Nolan, who had once starred alongside Orson Welles as Lady Macbeth. Nolan had also guest-starred on Gunsmoke more than any other woman, so she deserved this headlining role. She earned an Emmy nomination for this role, but it was no match for Sanford and Son. CBS pulled the plug before the Emmys were handed out.

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3

Getting Together

The Partridge Family
14 episodes

Teen idol Bobby Sherman and Wes Stern (how was he not a cowboy?) played Bobby Conway and Lionel Poindexter, two songwriters looking for the next big hit. The duo was modeled after real-life hit-crafters Boyce and Hart, who pop heads might remember as the team who penned smash singles for the Monkees. All-in-all, this was one big ball of late-Sixties pop. Maybe that's why it flopped in 1971. Kids were already moving on from bubblegum to hard rock.

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4

The Law & Harry McGraw

Murder, She Wrote
16 episodes

Jerry Orbach was a no-filter, old-school private dick. Barbara Babcock was an attorney. Together, they were a bit of "law and order." Or course, this Murder, She Wrote spin-off completely failed, leading Orbach to join Law & Order.

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5

Mr. T and Tina

Welcome Back, Kotter
5 episodes

When you hear "Mr. T," you think of gold chains, a mohawk and "I pity the fool." You do not think of Mr. Miyagi. Before all that Eighties pop-culture, in 1976, Pat Morita played a widowed Japanese inventor living in America with a governess named Tina taking care of his kids. Making this all the more confusing, Morita's character was named Taro Takahashi. Around the same time, he was playing Arnold Takahaski on Happy Days, a completely different character with the same surname. Audiences were uncertain which hit sitcom was doing the spinning off.

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6

The New Perry Mason

Perry Mason
15 episodes

Admittedly, this is a reboot, but we had to include it. Until the 2020 HBO remake of Perry Mason with Matthew Rhys, Monte Markham was the last man to play Erle Stanley Gardner's ace defense attorney. That's him on the right. Before landing the lead in The New Perry Mason reboot, Markham had played the title role in the TV adaptation of Mr. Deeds Goes to Town — not to mention guest roles on Mary Tyler Moore and more. Perhaps the most interesting casting of this fresh 1970s attempt to revive the character was Brett Somers, best known for her one-liners on Match Game, playing Gertie, Perry's receptionist. She was rarely seen on the original, but was fleshed out more here.

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7

Richie Brockelman, Private Eye

The Rockford Files
5 episodes

Jim Rockford was a cool guy, driving a cool car, living in a cool spot by the beach. "Richie Brockelman" had an uphill battle convincing people he was cool. RICHIE BROCKELMAN. Strikes fear in the hearts of criminals. With that name, he sounded more like the second-chair piccolo in the high school band. His character was introduced on The Rockford Files in the episode "The House On Willis Avenue." Richie returned for another case, "Never Send a Boy King to Do a Man's Job," but his own adventures never captured an audience. Star Dennis Dugan would go on to appear in loads of Adam Sandler movies.

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8

The Tortellis

Cheers
13 episodes

"Not just another family comedy. Not just another family," the ads declared. Not exactly. With its uncouth, blue-collar characters, The Tortellis brought to mind the Bundys of Married… with Children. That being said, this Cheers spin-off premiered a few months before that crass Fox sitcom. The story followed Nick Tortelli, Carla's ex, to Las Vegas with his blonde trophy wife, played by Jean Kasem (wife of radio man Casey Kasem). Elvis impersonators, Charo and guest-spots from Norm (George Wendt) could not save the show. After the show flopped, the characters moved back to Boston and returned to Cheers.

Image: The Everett Collection

9

W*A*L*T*E*R

M*A*S*H
1 episode

Just looking at the title, you can tell which series this potential spinoff came from. In fact, W*A*L*T*E*R wasn't a direct spinoff of M*A*S*H, but rather born of its ill-fated spinoff AfterMASH. Radar was now going by his given name, Walter, and living in St. Louis with his cousin and a rookie cop. CBS aired the pilot episode once, and even that broadcast was preempted in some markets by the Democratic National Convention.

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