One of the great strengths of TV is the ability to adapt and many important characters over the years have had humble origins. While story lines are meant to tell the audience how to react sometimes we end up rooting for a smaller character who might deserve more of the limelight. Here is a place for tributes to characters who broke out and became major thanks to strength of performance audience reaction etc... People might notice that a reoccurring theme for these characters is they are often diametrically different from the main character(s). There will be some minor spoilers, but I'll try to minimize them.
First the godfather of all breakthrough characters Doctor Fraser Krane (Kelsey Grammer) Cheers. A small character in the early days and unlikely romantic rival for the oh so cool Sam Malone. He ended up becoming so popular that he got his own spin-off and became one of the longest running characters in live action TV history.
Leopold 'Butters' Stotch South Park he is not even a character in the first couple years and only slowly started appearing as one of the background non characters who populate the school. Even in Bigger Longer and Uncut he only gets a couple tiny lines. It wasn't until they left Kenny dead (for awhile at least) and started looking at other characters to become the fourth kid that things shifted and even then it started as a novelty to give a character as small as Butters his very own episode, but things were never the same. He's a goody goody where the other characters are hard edged and the victim of many of their schemes and yet he might be the most #$@*ed up kid in that whole town.
Spike (James Marsters) Buffy the Vampire Slayer. I could do a whole list and never depart from that one series, all the one name characters (Angel, Faith, Wesley, Anya) were intended as smaller parts and yet all my real favorites from the Whedonverse sprung up from among them. They only get one name because they were not important enough to warrant anything more. Spike was the opposite of what vampires were expected to be as creatures of anachronistic style and manner and OCD in their ritualistic nature, and yet he was everything a vampire should be: smart, strong, resourceful, incredibly charming and manipulative. His insolent attitude often covered a nature which was strangely sentimental for a vampire and his frequent improvisations and surprise moves disguised great patience smart opportunism and capacity for long term planning. He was supposed to be killed off after just a few episodes, but he was such an instant favorite both among fans and the cast that they could not simply kill him off.
Let's be clear on something I do not @#@$ing consider the Spike as seen on Buffy season 5-7 to be him at all. Kept around to boost ratings he was the but of jokes and the whipping boy for the clique of four. Spike as he appeared in season 2 could have and would have wiped out the entire Harris family tree chip or no chip long before he would ever be at the mercy of a lout like Xander. This is one of thee worst transitions in the history of writing as it was both unnatural in its flow (in season 4 he is highly competent though fallible in season 5 he's just a dumb ass) and in its willful ignoring of the character's history and personality traits. So far as I'm concerned the renewed Spike who showed up in Angel season 5 was in that amulet for years and how he got there was never explained.
Lagertha (Katheryn Winnick) Vikings This one started as more of a secondary character (the actress was told by the network very specifically not to expect very much and that she was just there to play the wife), but as of the second season she was hugely expanded into more of a co-lead. The wives of the lead characters on TV are often hugely hated by fans (Carmela Soprano and Skyler White being good examples) but right from the start Lagertha was very different and compelling in her own rite. She balanced the warrior side with domestic concerns that allow her to be a bridge character for two sides of a single culture. When people obsess over Lagertha it actually feels natural and her influence and fame make perfect sense.
Boyd Crowder Justified, he is in every episode of the show despite having actually died in the pilot when he was shot in the center of the chest. But Walton Goggins was so great, and such a perfect juxtaposition to Timothy Olyphant's Raylan that the people spoke and they wanted more. So adding in a quick shot of him being brought out on an gurney at death's door, his death was changed to him just barely being saved by quick surgical intervention. He was so good that Elmore Leonard resurrected him in his books. A quick witted desperado with a flare for explosives it's hard to imagine the series without him.
Bronn (Jerome Flynn) Game of Thrones, the tightly plotted nature of this show is one of its greatest strengths but can also be a weakness, and many of the leading characters or only okay and many of the characters they've added or expanded on have been dodgy choices at best. Bronn is a rare exception in terms of coming to life like a scuzzy Errol Flynn, by now he would have been written out, but it seems they'll be keeping him close to important events for some time.
Jesse Pinkman (Aaron Paul) Breaking Bad was not supposed to survive the first season, and yet he managed to struggle and survive and evolve into a character of rare emotional depth. He seamlessly transitioned from two dimensional comic relief to a player in his own right (it's the perfect opposite of what was done with Spike).
Lilly Kane Veronica Mars, and the award for liveliest corpse in TV history goes to Amanda Seyfried. No one wanted to play this character since, in keeping with the plan, she was only going to be briefly shown in a flashback and then lying dead and then much later on a tiny clip of her on tape would appear. This is a death that could not be unwritten, and yet between dreams flashbacks hallucinations and tributes she's essentially a full cast member for the whole first season. Instead of a one dimensional idealized murder victim Lilly really came to life as someone to drive you crazy and still have you wanting to spend all your time with them. Rob Thomas even joked about wanting to bring her back for the movie, "There's dead dead and then there's TV dead."
Honorable mentions: Saul Goodman (Bob Odenkirk) Breaking Bad, Wynn Duffy (Jere Burns) Justified, Bobby Singer (Jim Beaver) Supernatural, Shelby (Jim Beaver) Justified repeat offender, Xena Warrior Princess (Lucy Lawless) Hercules the Legendary Journeys she started as a one off villain, and of course The Fonz (Henry Winkler) Happy Days.
First the godfather of all breakthrough characters Doctor Fraser Krane (Kelsey Grammer) Cheers. A small character in the early days and unlikely romantic rival for the oh so cool Sam Malone. He ended up becoming so popular that he got his own spin-off and became one of the longest running characters in live action TV history.
Leopold 'Butters' Stotch South Park he is not even a character in the first couple years and only slowly started appearing as one of the background non characters who populate the school. Even in Bigger Longer and Uncut he only gets a couple tiny lines. It wasn't until they left Kenny dead (for awhile at least) and started looking at other characters to become the fourth kid that things shifted and even then it started as a novelty to give a character as small as Butters his very own episode, but things were never the same. He's a goody goody where the other characters are hard edged and the victim of many of their schemes and yet he might be the most #$@*ed up kid in that whole town.
Spike (James Marsters) Buffy the Vampire Slayer. I could do a whole list and never depart from that one series, all the one name characters (Angel, Faith, Wesley, Anya) were intended as smaller parts and yet all my real favorites from the Whedonverse sprung up from among them. They only get one name because they were not important enough to warrant anything more. Spike was the opposite of what vampires were expected to be as creatures of anachronistic style and manner and OCD in their ritualistic nature, and yet he was everything a vampire should be: smart, strong, resourceful, incredibly charming and manipulative. His insolent attitude often covered a nature which was strangely sentimental for a vampire and his frequent improvisations and surprise moves disguised great patience smart opportunism and capacity for long term planning. He was supposed to be killed off after just a few episodes, but he was such an instant favorite both among fans and the cast that they could not simply kill him off.
Let's be clear on something I do not @#@$ing consider the Spike as seen on Buffy season 5-7 to be him at all. Kept around to boost ratings he was the but of jokes and the whipping boy for the clique of four. Spike as he appeared in season 2 could have and would have wiped out the entire Harris family tree chip or no chip long before he would ever be at the mercy of a lout like Xander. This is one of thee worst transitions in the history of writing as it was both unnatural in its flow (in season 4 he is highly competent though fallible in season 5 he's just a dumb ass) and in its willful ignoring of the character's history and personality traits. So far as I'm concerned the renewed Spike who showed up in Angel season 5 was in that amulet for years and how he got there was never explained.
Lagertha (Katheryn Winnick) Vikings This one started as more of a secondary character (the actress was told by the network very specifically not to expect very much and that she was just there to play the wife), but as of the second season she was hugely expanded into more of a co-lead. The wives of the lead characters on TV are often hugely hated by fans (Carmela Soprano and Skyler White being good examples) but right from the start Lagertha was very different and compelling in her own rite. She balanced the warrior side with domestic concerns that allow her to be a bridge character for two sides of a single culture. When people obsess over Lagertha it actually feels natural and her influence and fame make perfect sense.
Boyd Crowder Justified, he is in every episode of the show despite having actually died in the pilot when he was shot in the center of the chest. But Walton Goggins was so great, and such a perfect juxtaposition to Timothy Olyphant's Raylan that the people spoke and they wanted more. So adding in a quick shot of him being brought out on an gurney at death's door, his death was changed to him just barely being saved by quick surgical intervention. He was so good that Elmore Leonard resurrected him in his books. A quick witted desperado with a flare for explosives it's hard to imagine the series without him.
Bronn (Jerome Flynn) Game of Thrones, the tightly plotted nature of this show is one of its greatest strengths but can also be a weakness, and many of the leading characters or only okay and many of the characters they've added or expanded on have been dodgy choices at best. Bronn is a rare exception in terms of coming to life like a scuzzy Errol Flynn, by now he would have been written out, but it seems they'll be keeping him close to important events for some time.
Jesse Pinkman (Aaron Paul) Breaking Bad was not supposed to survive the first season, and yet he managed to struggle and survive and evolve into a character of rare emotional depth. He seamlessly transitioned from two dimensional comic relief to a player in his own right (it's the perfect opposite of what was done with Spike).
Lilly Kane Veronica Mars, and the award for liveliest corpse in TV history goes to Amanda Seyfried. No one wanted to play this character since, in keeping with the plan, she was only going to be briefly shown in a flashback and then lying dead and then much later on a tiny clip of her on tape would appear. This is a death that could not be unwritten, and yet between dreams flashbacks hallucinations and tributes she's essentially a full cast member for the whole first season. Instead of a one dimensional idealized murder victim Lilly really came to life as someone to drive you crazy and still have you wanting to spend all your time with them. Rob Thomas even joked about wanting to bring her back for the movie, "There's dead dead and then there's TV dead."
Honorable mentions: Saul Goodman (Bob Odenkirk) Breaking Bad, Wynn Duffy (Jere Burns) Justified, Bobby Singer (Jim Beaver) Supernatural, Shelby (Jim Beaver) Justified repeat offender, Xena Warrior Princess (Lucy Lawless) Hercules the Legendary Journeys she started as a one off villain, and of course The Fonz (Henry Winkler) Happy Days.