Sitcom guest stars come in a few varieties. There are the superstars who go slumming in an effort to boost ratings and wink-wink their way through an appearance. There are the lifelong character actors forever destined to play “the weird goofy guy," “the weird creepy guy” or “the weird nebbish guy." And then there are the actors who take any bit part they can get their hands on, with the chance that someone, somewhere might want to build a series around them. That’s what eventually happened to these Guest Stars Who Became Stars of Their Own TV Shows.

  • Jane Lynch

    ‘Frasier’ (1996)

    Years before she put on a track suit and became a Gleek’s ultimate nemesis, Jane Lynch had a long spell as “that woman.” She was that woman on the Frosted Flakes commercial. She was that woman in ‘The Fugitive.’ And, by the late ’90s, she was that woman on a whole bunch of sitcoms -- including a 1996 episode of ‘Frasier,’ in which she played a well-to-do parent named Cynthia. It’s amusing to look back at Sue Sylvester with longer hair and affecting a WASPy accent and upper-crust attitude. Lynch would endure the guest-star domain a while longer, although her career got a big boost when Christopher Guest directed a commercial she was in and decided she would be a perfect addition to 2000’s ‘Best in Show.’ That led to two more Guest-directed movies and, eventually, her starring turn in ‘Glee.’

  • John Mahoney

    ‘Cheers’ (1992)

    Less than a year before the premier of ‘Frasier,’ John Mahoney made a one-off appearance on the final season of ‘Cheers’ -- but not as Frasier’s father, the irascible Martin Crane. With his hair slicked back and a hideous blazer on his shoulders, Mahoney turned up as Sy Flembeck, the ad man who will write your business a jingle for 200 bucks. When Rebecca Howe (Kirstie Alley) takes him up on the deal on behalf of Cheers, she discovers that every song this shyster writes is to the tune of a children’s song. Oh, and that Sy spells Cheers C-H-E-R-S. Fortunately, Dr. Frasier Crane didn’t get mixed up in the shenanigans, or the sitcom space-time continuum might have been blown to smithereens.

  • Matthew Perry

    ‘Charles in Charge’ (1985)

    Nearly a decade before Matthew Perry became one of the highest-paid TV actors with his role as Chandler Bing on ‘Friends,’ one of his first sitcom roles was as a potential suitor for Lila Pembroke on ‘Charles in Charge.’ Unfortunately, Perry was given the unenviable position of playing the respectable alternative to the obnoxious guy that Lila wants to date, Van (Gary Riley). While Perry’s muttering something about Princeton, Riley is smacking his bubble gum, bragging about his “rock group” the Scuzz and generally being a sanitized version of an ’80s bad boy. Perry never stood a chance … and could he be wearing an uglier sweater?

  • Lisa Kudrow

    ‘Cheers’ (1989)

    Another ‘Friend’ got a slightly meatier role for her sitcom debut when Lisa Kudrow appeared on ‘Cheers’ in 1989. The future Phoebe Buffay played eager method actor Emily, who was co-starring with Woody Boyd (Woody Harrelson) in a play. It’s interesting to see some of Kudrow’s Phoebe mannerisms manifest in Emily, who is less ditsy (but less likable). Kudrow would earn parts on a number of other shows, including ‘Mad About You.’ Starting in 1993, she had a recurring role as heartless waitress Ursula Buffay, who – in a 1995 crossover episode – would be revealed as Phoebe’s twin sister.

  • Amy Poehler

    ‘Undeclared’ (2001)

    In the short window between Comedy Central’s ‘Upright Citizen’s Brigade’ sketch series and her time on ‘Saturday Night Live,’ Amy Poehler showed up for a few episodes on the late, great ‘Undeclared.’ Long before she was Leslie Knope, Poehler played flirtatious top floor R.A. Hillary on Judd Apatow’s follow-up to ‘Freaks and Geeks.’ ‘Undeclared’ wouldn’t make it past its first season, but ‘SNL’ would make the funnywoman a star – although Poehler would still find time to guest star as Gob’s nameless wife on ‘Arrested Development.’

  • Harry Anderson

    ‘Cheers’ (1982)

    Two years before he became the Honorable Harry T. Stone on ‘Night Court,’ Harry Anderson was on the other side of the law as con man Harry “the Hat” Gittes on the first season of ‘Cheers.’ With a name stolen from ‘Chinatown’ and a talent for sleight-of-hand pilfered from Anderson’s own magic act, Harry the Hat was always getting run out of Cheers by Sam Malone (Ted Danson) for taking money from the bar’s patrons … OK, mostly Cliff and Norm. Even after his ‘Night Court’ success, Anderson returned to the Boston bar a couple of times – most notably for the series’ final ‘Bar Wars’ episode.

  • Michael Richards

    ‘Night Court’ (1984)

    Speaking of ‘Night Court,’ there were few series that provided more reliable opportunities for outlandish acting – what with the constant parade of wackos being prosecuted by Dan Fielding (John Laroquette). So it only makes sense that Michael Richards would appear during the NBC sitcom’s second season as Eugene Sleighbough, a man who is convinced he is invisible. Richards, who chews his share of scenery with a hammy performance, would bounce around from dramatic to comedic series throughout the ’80s before discovering pop culture immortality as the one and only Cosmo Kramer on ‘Seinfeld.’

  • Bryan Cranston

    ‘Seinfeld’ (1994)

    For years, Bryan Cranston played one of the most evil, megalomaniacal villains in television history. Wait, Walter who? No, we’re talking about Dr. Tim Whatley – the re-gifting, nitrous oxide-inhaling dentist who converted to Judaism just for the jokes! During ‘Seinfeld’s epic run, Cranston’s Dr. Whatley appeared on five episodes, including ultimate classics ‘The Jimmy’ and ‘The Yada Yada.’ Not long after the show ended, Cranston became beloved TV dad Hal on ‘Malcolm in the Middle’ – although it was a 1998 guest spot on ‘The X-Files’ that helped him earn the central role on ‘Breaking Bad,’ along with an armful of Emmys. We guess the Academy of Television Arts and Sciences aren't a bunch of anti-dentite bastards.

  • Jerry Seinfeld

    ‘Benson’ (1980)

    Before starring on his eponymous sitcom, Jerry Seinfeld’s television appearances were mostly limited to stand-up spots on talk shows. But the comedian did appear in three episodes during the second season of ‘Benson’ in 1980. Seinfeld played Frankie, the courier who was always trying to get past Benson (Robert Guillaume) in order to sell corny jokes to the governor. So basically, this was a poorly disguised attempt to have an up-and-coming comic spit out a few one-liners and beef up the show’s plot-to-laughs ratio. Hardly a natural actor, Seinfeld would do much better playing himself a decade later.

  • David Letterman

    ‘Mork and Mindy’ (1979)

    A few years before ‘Late Night With David Letterman’ became one of the coolest shows on TV, its host portrayed a cantankerous self-help guru for one of the first-season episodes of ‘Mork and Mindy.’ Letterman played the nasty Ellsworth, a weasel obsessed with money and insulting his followers, and who eventually gets told off by Mork (Robin Williams). It’s strange to see Dave in gold chains and a leisure suit, although the character allowed him to draw on his inherently edgy persona. “Nanoo nanoo” aside, it’s safe to say that Letterman didn’t miss out on being one of TV’s great character actors by taking the ‘Late Night’ hosting job instead.

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