Chris Langham quickly disappeared from The Thick of It after he was convicted of child porngraphy possession, but the series continued for several more seasons with a new inept politician as the lead role.
I don’t know about “biggest,” but how about Lisa Bonet and That Show You Left Turned On Your TV After The Cosby Show So You Wouldn’t Miss Cheers - er, A Different World ?
Well, more promoted than quit - she got her own spin-off that lasted two seasons (the first very abbreviated) before being cancelled.
And Solar Opposites, where again he dominated the voice work. Fired more or less simultaneously from two shows has to be some sort of achievement award.
Of course Wilmer Valderrama got lucky and was cast on NCIS for seven seasons so far.
I think there are multitudes of actors who would equate “plenty of work” with doing really well, but I get your point.
Bonert left Different World after one season and the show had five seasons after that, so it kept going pretty well. Her departure was also pregnancy related.
I wouldn’t say that she quit, exactly. She left to star in a spin-off, called Flo. Unfortunately it only lasted a single season, and is pretty much forgotten today (even more so than Alice itself). But the motive for leaving seems a bit different than actors who just leave on the vague hope of getting movie offers.
David Caruso left NYPD Blue after the second season because they wouldn’t give him a sizeable raise. It kept going 10 more seasons after that.
True story: a friend of mine worked as a production assistant on that show and was sent out to pick up a coffee order. It took her a moment to realize why the cashier gave her such a strange look when she said “Hi, I’m from A Different World.”
Thomas Gibson was kicked off of Criminal Minds after an altercation with someone on the set.
Mandy Patinkin also left Criminal Minds, though at his own choice.
Michael Moriarty had a fairly acrimonious split when he left Law & Order.
Jeremy Clarkson was kicked off the British auto show Top Gear after a “fracas” with a producer of the show, along with issues of general ass-hattery. His other two stars quit at the same time. The show kept going for several years, although it was not as popular.
And then Amazon paid them boatloads to do basically the same show on Prime, rebranded as The Grand Tour. I’m sure Clarkson was fine getting away from the politics of the BBC.
Not a big star but the recent Lethal Weapon TV series with Clayne Crawford as Riggs and Damon Wayans as Murtaugh apparently fired Clayne after Season 2 because he was such a piece of shit on set and killed off the character so Season 3 (the final season) they gave an entirely new character/actor as partner to Murtaugh.
Which if you think about it is absolutely bizarre, the entire point of the show is that it’s supposed to be a TV retelling of the movies but apparently the main actor is so hard to work with it was easier to just kill off the actual legendary film character of Riggs than to just recast him. It’s like if the actor who played Batman was such an asshole they killed off Batman in his own show.
And considering he is not a convicted rapist and a group that talked about the “great character” of a convicted rapist… Topher’s doing pretty good since he’s never really been hated or been toxic…