During my layoff (during Covid's height) I caught up on all kinds of shows/movies and one of the shows was Parks and Recreation (I went in completely blind, as for some reason I never caught a single episode or was even aware of the cast). I was surprised when they added Ben and Chris and just how much they elevated an already good show.

So, what cast additions surprised you with how well they worked, what are some that were terrible? We can even talk about cast subtractions that had the same effect.

Cheers is a masterclass in good casting.

The additions of Kirstie Alley, Woody Harrelson, Kelsey Grammer, and Bebe Neuwirth pushed the show into the stratosphere (and #1 in the ratings), and if I'm being totally honest, the Sam/Diane angle had been pretty much played out, so the loss of Shelley Long was really no loss at all.

Jeri Ryan to Star Trek: Voyager.

They were doing some interesting stories for the first three seasons but she came in and (besides bringing her cheesecake appeal, which was considerable) she fucking blew the doors off the rest of the cast excepting Robert Picardo (The Doctor).

Not only did her character give the writers something really interesting to dig into, but she had the chops to make it believable and when paired with the aforementioned Picardo, they nearly dominated the show for the rest of its run.


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Sidebar: do we want to get into Doctor Who? Because a changing cast was part of the show since the very beginning. I will say Jenna Coleman was there with two different Doctors and she had helluva presence for like three seasons. And then the addition of Michelle Gomez as Missy was a goddamn masterstroke of casting.

NYPD Blue did a great job replacing detectives as the show went on.

Reverend Jim added to the cast of Taxi.

Not only was it not a loss, it was actually an improvement (even without anyone replacing her). It was addition by subtraction.

I might be in the minority here, but I think the addition of Amy and Bernadette to Big Bang Theory was great. I liked the characters and it really opened up the story lines.
Although Amy was horrible the first bunch of episodes when she was a robot/Sheldon clone. Luckily they opened up her character to being human and also very horny.

Great example. I always forget he was addition to the cast, he was so good I always think of him as being there from day one.

I mean they also subtracted Blandanwitch so it was like a double whammy.

Devito added to always Sunny as well. In fact I swear we did this thread idea already.

But yeah Cheers has to take the cake.

Best addition: Spike on Buffy The Vampire Slayer
Worst addition: Connor on Angel

I know the Charmed reboot wasn't a big hit but once the character of Macy left it sucked for the last season.

Had to look it up. That shit got 4 seasons? I bailed early in the first season.
But, since you mentioned Charmed, the original, fits the thread. I liked Rose McGowan better than Shannen Doherty on the show. I know, there are probably others that feel the opposite. I was just never a big fan of Shannen.

I actually liked the Charmed reboot. The last season wasn't the greatest though. I also prefer Rose McGowan over Doherty in the original show. I am actually rewatching Charmed and just started season six.

The OP picked the best example with the additions of Rob Lowe and Adam Scott to Parks and Rec.

Sadie Sink added to Stranger Things in Season 2 is another one that comes to mind. She's probably the best young actor in that whole bunch IMO.

Does Fring count in Breaking Bad?

Worst addition BTVS: A tie between Riley(Buffy's b/f) and Tara (Willow's g/f)beginning in season 4.

Don’t see why he wouldn’t. Good choice.

Ill say Devito on it’s always sunny for my favorite.

Also - Bill Murray and Eddie Murphy for being the first and most important additions to SNL.

Fred on Angel, and then later Spike on Angel

ER went through so much change there are likely five great additions and five lousy additions to list, but I was thinking of Maura Tierney in particular as a great addition.

Not from the very beginning of course. New companions started after Carole Ann Ford decided to leave and was then replaced with a different character. Replacing The Doctor didn't come up until William Hartnell couldn't really do the role any longer by the end of season 3.

Season 1 was... not good.
Season 2 was an improvement but was still pretty mediocre

If they hadn't added Lowe and Scott, it probably would have been canceled after season 3.

How about Best AND Worst addition with a single character?

Chloe on 24. She was insufferable, obnoxious, annoying and just generally a terrible character in her first season. By the end of it's run though she had made a a complete 180 and you couldn't imagine the show without her.

Riley was a complete charisma sink and had absolutely no chemistry with SMG. It's mystifying to me how Riley's actor ended up having steady jobs after the show.

Like the OP, I just recently watched 'Parks & Rec' for the first time. Overall, I thought it was decent enough, but not great. By far, my two favorite characters were Ron and April, with their droll humor.

Agree that adding Adam Scott and Rob Lowe were huge additions. Conversely, the added character of Craig in the last couple season was awful. Overly dramatic yelling of every line does not equal comedy. (See: Leslie Jones.)

Yeah, I wasn't a fan of Craig on Parks & Rec.

Isn't there some domino effect theory that the success of Jeri Ryan on Voyager was eventually responsible for the presidency of Barack Obama?

Ill say Ed Helms to the office was a great addition.