A role can make or break an actor's career, but the right choice of actors can also determine the show's success. For example, Grey's Anatomy might never have reached its 19th season if their casting for Meredith hadn't been spot on.
There are a lot of actors auditioning for all kinds of roles, but it's most interesting to think about the iconic roles because a different casting really would have changed the final outline of the show. So casting directors are doing their best to find the very best fit for their vision of the character, and most times it works.
Iwan Rheon as Jon Snow
Actor Iwan Rheon first auditioned for the part of Jon Snow on Game of Thrones. He was most known for his role as Simon in the Misfits UK series, which he did a fantastic job at. He admitted that his Jon Snow would have been a lot different if he'd gotten to play him and said they made a good choice.
No bad blood was left between them because Rheon ultimately got his shining moment on the show, even if it was as the villainous Ramsay Bolton. Apparently, he has a knack for portraying characters that are somewhat out of the ordinary.
Taylor Momsen as Hannah Montana
Love her or hate her, Hannah Montana is an iconic character, brought to life masterfully by Miley Cyrus. But she wasn't the only one who was in the running. She was actually one of the three final choices, as the casting director mentioned here, including Taylor Momsen.
This is hard to wrap one's head around, because of her current aesthetic. One of her first roles was the sweet Jenny Humphrey on Gossip Girl, who eventually became one of the most hated supporting characters. It would've been interesting to see her pull it off. Still, Cyrus did an incomparable job with the character and the rest was history.
Nathan Fillion as Angel
Both roles of Buffy and Angel almost went to somebody else initially. Fillion auditioned for Angel, and didn't make the first cut, as he recalled. Joss Whedon apparently even felt bad because he didn't remember his audition, though it's very unlikely he would have been present during the first round.
Fillion did get his part after a while when he was cast as the First Evil or Caleb. The villain who did more damage than everyone combined to the core group of the show, and Fillion did an amazing job at it, before moving on to less villainous roles like Richard Castle, and most recently John Nolan on The Rookie.
Katie Holmes as Buffy
Before Sarah Michelle Gellar booked the part of Buffy, other actresses auditioned and were in the running. One of them was none other than Dawson's Creek alumna Katie Holmes as revealed here. The audition for BTVS happened before Holmes was cast as Joey, and she turned the role down.
It's interesting to think how her being cast could have changed the show altogether. From her portrayal of Joey, it's safe to assume her interpretation of Buffy might have been a bit gentler than Gellar's. But both of them ultimately ended up right where they needed to be.
Jennifer Lawrence as Serena Van Der Woodsen
Serena Van Der Woodsen was an iconic character that teenagers adored and wanted to be just like her. But the character was almost portrayed by a different actress. Many actresses auditioned for the part, including the now-famous Jennifer Lawrence, who didn't get the part.
But Blake Lively was a perfect Serena, and it's hard to imagine someone else in the role, even if Lawrence has proven herself in an impressive array of roles over the years. Getting the role could have importantly impacted Jennifer Lawrence's career if this meant she leaned more into television than movies.
Rob Lowe as Derek Shepherd
McDreamy almost looked different from the way everyone knew. Low didn't even have to audition to be offered the part, but according to him, he was skeptical about joining the cast because ABC's dramas had a pendant for failing, so he decided to give Dr. Vegas a chance instead.
In the same anecdote, he relays that he actually liked the script and thought it was fresh and crisp but didn't want to risk it. Despite his reservations about ABC, he later played Robert McAllister in Brothers and Sisters.
Elizabeth Olsen as Daenerys Targaryen
In a podcast, Elizabeth Olsen recalled auditioning for one of the most iconic TV roles, Daenerys Targaryen, a.k.a. the Mother of Dragons. Elizabeth is a fantastic actress and, at the moment, a significant part of the MCU franchise, which includes some of her best movies, but she felt very awkward at the audition.
The talented actress didn't even get a callback after her audition, which was Daenerys' speech after emerging from the fire. The role instead went to a relatively unknown Emilia Clarke, who made it her own, while Olsen went on to portray Wanda Maximoff.
Kristin Davis as Monica Geller
In an interview, Kristin Davis, better known as the fabulous Charlotte from Sex and the City, recalled reading for the part of Monica Geller on Friends. According to her, they were friends then, and she even found out she lost the part while they were on a shopping trip.
It can be argued that things turned out for the best because even though Cox originally read for the part of Rachel, she was the perfect Monica, and likewise, Davis brought something unique to the role of Charlotte, and there were episodes that were especially great for fans of her character.
Octavia Spencer as Donna Meagle
The excellent Octavia Spencer was in the running for the role of office manager Donna Meagle on Parks and Recreation. Even though Retta was perfection in the role, and one of her scenes caused a viral meme that's still popular today, they were pretty neck and neck.
One significant thing to notice is that if Spencer had been chosen for the role, she might not have been available to shoot The Help, which was one of her best movies. It brought her a much-deserved Oscar win and opened up opportunities for her to try things other than comedy.
Selma Blair as Joey Potter
Selma Blair, who is perhaps the most famous for her role of Vivian in Legally Blonde, auditioned for the role of Joey Potter in Dawson's Creek. Creator Kevin Williamson said she was a serious contender for the role until he got Holmes' last-minute audition tape.
Due to her recent MS diagnosis, she hasn't been acting as much, but she was on Dancing With The Stars and even wrote a memoir titled "Mean Baby. Obviously, she's not dwelling on the roles she didn't get and instead focusing on the future.
Source:gamerant.com