The Magic Behind Harry Potter: Casting the Iconic Trio and Their Early Careers

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Ah, the Harry Potter franchise. It’s incredible how it’s still a mainstay in pop culture after all these years. The franchise continues to evolve beyond the annual movie marathons and the HBO 20th Anniversary special.

In 2023, a major reboot was announced. A new TV series will adapt each of the seven books in detail and aim for a 2026 release. This new project reflects the ongoing influence and reinvention of the Wizarding World for new generations.

Rupert Grint, Daniel Radcliffe, and Emma Watson at the Hand, Foot, and Wand-Print Ceremony at Grauman's Chinese TheatreRupert Grint, Daniel Radcliffe, and Emma Watson at the Hand, Foot, and Wand-Print Ceremony at Grauman’s Chinese Theatre on July 8, 2007, in Hollywood, California (Carrie Nelson / Shutterstock)

It’ll be intriguing to see how much further the Harry Potter series can go, especially with the upcoming reboot, and where the careers of its now-grown stars will lead.

The original actors, who delivered such compelling performances at a young age, left an indelible mark on the franchise. Let’s explore how old each of these young stars was during filming and what made them the perfect choices for their iconic roles.

The Casting Journey: How the Iconic Harry Potter Trio Was Discovered

Imagine being Christopher Columbus working on the first Harry Potter movie. You and your crew are responsible for picking child actors for an iconic series that must play these characters for a decade’s worth of movies.

Emma Watson as Hermione Granger, Rupert Grint as Ron Weasley, and Daniel Radcliffe as Harry Potter in the 2001 fantasy film Harry Potter and the Philosopher's Stone (also known as Harry Potter and the Sorcerer's Stone)Emma Watson as Hermione Granger, Rupert Grint as Ron Weasley, and Daniel Radcliffe as Harry Potter in the 2001 fantasy film Harry Potter and the Philosopher’s Stone (also known as Harry Potter and the Sorcerer’s Stone) (Credit: Warner Bros. Pictures)

That’s a heavy responsibility! In 2000, it took seven months of searching before Daniel Radcliffe, Emma Watson, and Rupert Grint were chosen for the roles.

Producer David Heyman and writer Steve Kloves discovered Radcliffe in a theater. He already had a role in a BBC production of David Copperfield.

Emma Watson and Rupert Grint had no on-screen experience and had only performed in school plays.

Daniel Radcliffe was 12 years old when the first Harry Potter movie based on J. K. Rowling's 1997 novel of the same name premiered in November 2001Daniel Radcliffe was 12 years old when the first Harry Potter movie based on J. K. Rowling’s 1997 novel of the same name premiered in November 2001 (Credit: Warner Bros. Pictures)

In hindsight, the casting is super impressive – it takes a keen eye to find talent like that, and the three never really had any big scandals either, so they got lucky in that department, too! Big props to casting director Janet Hirshenson for finding these talented kids.

Interestingly enough, Christopher Columbus stipulated that all the actors that were cast HAD to be British. He stuck to that rule hard, and even turned down Robin Williams for the role of Hagrid because of it!

The filmmakers all really wanted all of the characters to look authentic.

They ended up trying to give Daniel Radcliffe green contact lenses to match Harry’s description. Reportedly, the casting team had trouble finding the right actor because so many of the kids who auditioned had brown eyes and just wouldn’t have been able to wear the colored contacts because their eyes were too dark.

Daniel Radcliffe had an allergic reaction to the green color contacts he was supposed to wear in the movieDaniel Radcliffe had an allergic reaction to the green color contacts he was supposed to wear in the movie (Credit: Warner Bros. Pictures)

As it turns out, Daniel ended up having an allergic reaction to the green color contacts. While Harry Potter had green eyes in Rowling’s books, the author agreed to let Potter have blue eyes in the films.

He also has a nickel allergy and was allergic to the first pair of glasses he wore in the movie.

“It was brilliant because we put the glasses on and eventually we realized that I was allergic to them,” Radcliffe said about his first pair of Potter glasses.

“I was actually allergic to the Harry Potter glasses. Because I had these two rings of whiteheads and spots that had come up around my eyes and it took us a week to realize that it was actually the glasses.”

Chosen for their uncanny resemblance to the beloved characters, Daniel Radcliffe, Rupert Grint, and Emma Watson captured the essence of Harry, Ron, and Hermione from the very start, bringing J.K. Rowling's magical world to lifeChosen for their uncanny resemblance to the beloved characters, Daniel Radcliffe, Rupert Grint, and Emma Watson captured the essence of Harry, Ron, and Hermione from the very start, bringing J.K. Rowling’s magical world to life (Credit: Warner Bros. Pictures)

In addition to that, they also wanted Emma Watson to wear fake buck teeth to better look like the nerdy Hermione. However, Radcliffe’s eyes had a bad reaction to the contacts and Watson had trouble speaking with the buck teeth in, so those ideas were eventually discarded.

Daniel Radcliffe’s Age When Filming Harry Potter: A Glimpse into His Early Career

When Radcliffe was in Harry Potter and the Sorcerer’s Stone, he was only eleven years old – he turned twelve around when the movie was released.

Funnily enough, he really wasn’t interested in playing Harry Potter at first at all! After his role in David Copperfield, he intended to quit acting altogether.

His parents wanted him to quit and focus on schoolwork, too. However, producer David Heyman was able to convince him (and his parents) otherwise.

Maggie Smith as Betsey Trotwood and Daniel Radcliffe as David Copperfield in the 1999 BBC television drama adaptation of Charles Dickens's 1850 novel David CopperfieldMaggie Smith as Betsey Trotwood and Daniel Radcliffe as David Copperfield in the 1999 BBC television drama adaptation of Charles Dickens’s 1850 novel David Copperfield (Credit: BBC)

Here’s a fun fact – Richard Harris, who played Albus Dumbledore, often had trouble remembering his lines.

Reportedly, Daniel Radcliffe would purposely ask Harris for help running his lines just so Harris could get more practice.

What a sharp thing for an eleven-year-old to do! Incidentally, the main reason Harris took on the role was because his eleven-year-old granddaughter told him that she’d never speak to him again if he turned down Dumbledore. Harsh!

Rupert Grint’s Casting Story and His Age When He Became Ron Weasley

The story of how Rupert Grint was cast as Ron Weasley is so fun. He actually performed a rap about himself and taped it to send into the studio!

He also did a sketch dressed as his female drama teacher and then a video in which he actually read some lines as Ron. Rupert Grint was eleven years old when he was cast and when Harry Potter and the Sorcerer’s Stone was filming.

Rupert Alexander Lloyd Grint was 13 years old when Harry Potter and the Philosopher's Stone was released in November 2001Rupert Alexander Lloyd Grint was 13 years old when Harry Potter and the Philosopher’s Stone was released in November 2001 (Credit: Warner Bros. Pictures)

He said that Harry Potter had actually been his favorite book series growing up and that Ron was always his favorite character. What a lucky kid to be able to play him on the big screen!

It’s funny, though, because Grint’s ambition in life was not really to be an actor. In fact, his dream was to become an ice cream man.

So, after he cashed some Harry Potter checks, he went out and bought an ice cream truck of his own and drove it around to give out free ice cream.

Emma Watson’s Casting and Her Age During the First Harry Potter Film

According to Janet Hirshenson, there really weren’t that many actresses who were seriously in the running for Hermione, even though thousands applied.

She went on to say that the hardest part about casting Hermione was that they had to find someone who could play an annoying know-it-all without being too annoying – the audience still had to find her lovable.

Emma Watson was truly the one that swept the casting directors and producers away. She told Huffington Post, “As soon as Emma came on, there were six of us in the screening room. We just gasped. It was like, ‘Oh my God.’ Like, ‘Whoaaa!’

Emma Charlotte Duerre Watson was 11 years old when Harry Potter and the Philosopher's Stone was released in November 2001Emma Charlotte Duerre Watson was 11 years old when Harry Potter and the Philosopher’s Stone was released in November 2001 (Credit: Warner Bros. Pictures)

She took up the screen.” She was ten at the time she was cast, which made her eleven during the filming of Harry Potter and the Sorcerer’s Stone.

Fun fact: Emma Watson reportedly hated the way they styled her hair in the first movie. Eventually, the makeup department relented and let her have a less bushy hairstyle in the later films.

Tom Felton: From Auditioning for Ron Weasley to Becoming Draco Malfoy

Believe it or not, Tom Felton actually initially auditioned to be Ron Weasley. He auditioned to play Harry, too! But, of course, Felton landed the role of Draco Malfoy.

It’s hard to imagine him playing a Weasley, isn’t it? Felton jokingly said on MTV News that he was jealous of Rupert Grint and Daniel Radcliffe for being cast in their roles.

But then he clarified and said they were all friends throughout filming, right from the start, with no hard feelings.

Thomas Andrew Felton was 14 years old when Harry Potter and the Philosopher's Stone was released in November 2001Thomas Andrew Felton was 14 years old when Harry Potter and the Philosopher’s Stone was released in November 2001 (Credit: Warner Bros. Pictures)

Harry Potter was not Felton’s first film role. When he was ten years old, he appeared in the 1997 adaptation of The Borrowers.

Funnily enough, Jim Broadbent plays Felton’s father in that movie – and Broadbent would later be cast in the Harry Potter movies as Horace Slughorn!

Tom Felton as Peagreen Clock in the 1997 fantasy comedy film The BorrowersTom Felton as Peagreen Clock in the 1997 fantasy comedy film The Borrowers (Credit: Working Title Films)

Tom Felton was thirteen years old when Harry Potter and the Sorcerer’s Stone began filming in 2000. Felton said he actually was allowed to keep a few things from the set and still has those mementos.

They include Draco’s Slytherin ring and a tie pin from the set. Of course, the production team wouldn’t let the actors keep anything too showy – they all wanted to take their wands home, but that was out of the question!

During the 2022 reunion special film Harry Potter 20th Anniversary: Return to Hogwarts, Emma Watson admitted she was in love with Tom Felton during the filming of Harry Potter.

Daniel Radcliffe and Emma Watson in the 2022 reunion-special-film Harry Potter 20th Anniversary: Return to HogwartsDaniel Radcliffe and Emma Watson in the 2022 reunion special film Harry Potter 20th Anniversary: Return to Hogwarts (Credit: HBO)

“I walked into the room where we were having tutoring,” she said. “The assignment that had been given was to draw what you thought God looked like, and Tom had drawn a girl with a backward cap on a skateboard. And I just don’t know how to say it — I just fell in love with him.”

“I used to come in every day and look for his number on the call sheet, it was number seven, and if his name was on the call sheet, it was an extra exciting day. He was three years above me and so for him, he was like, ‘you’re like my little sister.’”

The Real Reason Chris Columbus Left the Harry Potter Franchise

To this day, people are still shocked that Chris Columbus would step down from helming such a beloved franchise. I mean, he was pretty much set to make big banking movies for life if he had stuck with it!

In the end, though, after Sorcerer’s Stone and Chamber of Secrets, Columbus said he was just too emotionally exhausted. They are all huuuuge movies after all, with the first film taking 160 days of shooting and the second being about 160 days as well.

He ultimately decided that he needed to take care of his mental health and take time off, and plus he wanted to make sure he could be home to watch his four kids grow up.

Chris Columbus and Robbie Coltrane at the premiere of "Harry Potter and The Prisoner of Azkaban"Chris Columbus and Robbie Coltrane at the premiere of “Harry Potter and The Prisoner of Azkaban” held at Radio City Music Hall in New York City on May 18, 2004 (Credit: Albert Ferreira / Startraksphoto)

That being said, Columbus said he wouldn’t be against returning to the Harry Potter franchise. He said that he would be willing to come back if there was ever an adaptation of Harry Potter and the Cursed Child.

After Columbus left, quite a few other directors stepped in to fill in for director. Prisoner of Azkaban was directed by Alfonso Cuarón, Goblet of Fire was Mike Newell, and then the remaining four films were directed by David Yates.

Ranking the Harry Potter Films: Which One Stands as the Best?

Now for the ultimate question: which Harry Potter movie is the best? Well, according to Rotten Tomatoes’ critical aggregate score, the answer is Harry Potter and the Deathly Hallows: Part 2 with a 96%.

That film ended the series so perfectly, and it felt so good to see the film series thrive for all those years and then finish off with a fantastic conclusion.

Emma Watson, Daniel Radcliffe, and Rupert Grint at the premiere of "Harry Potter and the Chamber of Secrets"Emma Watson, Daniel Radcliffe, and Rupert Grint at the premiere of “Harry Potter and the Chamber of Secrets” at the Ziegfeld Theatre in New York on November 10, 2002 (Credit: Albert Ferreira / Startraksphoto)

The worst-rated? Well, actually, it’s Fantastic Beasts: The Crimes of Grindelwald, with an abysmal 36% critical score and only a 54% audience score.

All of the movies in the mainline Harry Potter sequels are certified fresh, though!

Emma Watson’s Stunning Lace Dress and Feathered Look at the Harry Potter Premiere

Emma Watson shows off her open back Rafael Lopez for Atelier Mayer dressEmma Watson shows off her open-back Rafael Lopez for Atelier Mayer dress (Credit: WENN / Lia Toby)

In November 2010, the all-grown-up Emma Watson flaunted her legs at the London premiere of Harry Potter and The Deathly Hallows: Part 1, the first of two cinematic parts based on J. K. Rowling’s 2007 novel of the same name.

Emma Watson rocks a stunning pixie haircutEmma Watson rocks a stunning pixie haircut (Credit: WENN / Lia Toby)

Didn’t she look fabulous? The former child star was growing up to be a style star.

Emma Watson flaunted her legs in a Rafael Lopez vintage lace dress with a feathered skirtEmma Watson flaunted her legs in a Rafael Lopez vintage lace dress with a feathered skirt (Credit: WENN / Lia Toby)

Her lace dress with ostrich feathers was simply divine. Well, at least it appeared that way on her.

Emma Watson shows off her Solange Azagury-Partridge weapon earrings and a Royal British Legion paper poppyEmma Watson shows off her Solange Azagury-Partridge weapon earrings and a Royal British Legion paper poppy (Credit: WENN / Lia Toby)

Combining her pixie haircut with the dress made her look oh-so-mod and stylish. And even though Emma didn’t wear anything underneath the dress save for a bra, she surprisingly didn’t look tacky. The patterns on the dress were enough to cover her to decency.

Emma Watson rocks black Charlotte Olympia Esmerelda pumpsEmma Watson rocks black Charlotte Olympia Esmerelda pumps (Credit: WENN / Lia Toby)

But you know what my favorite part was? The back. I love dresses with high fronts and low backs, and this is one of them.

The dress is by Rafael Lopez and was designed for the house of Atelier Mayer. She styled her tie-back dress with Charlotte Olympia heels.

Daniel Radcliffe, Emma Watson, and Rupert Grint at the World Premiere of 'Harry Potter and the Deathly Hallows Part 1'Daniel Radcliffe, Emma Watson, and Rupert Grint at the World Premiere of ‘Harry Potter and the Deathly Hallows Part 1’ held at the Odeon Leicester Square in London on November 11, 2010 (Credit: WENN / Lia Toby)