'Harry Potter' stars James and Oliver Phelps didn't know which Weasley twin they were playing until right before filming the first movie

• James and Oliver Phelps played Fred and George Weasley in the "Harry Potter" films.
• The twins weren't sure which Weasley boy they were playing until right before filming started.

Actors James and Oliver Phelps apparently had no clue which Weasley twin they were playing until minutes before the first table read for "Harry Potter and the Sorcerer's Stone."

The brothers, who played Fred and George, now host the podcast "Normal Not Normal," on which they interview fellow actors and divulge behind-the-scenes secrets from the films.

They sat down with costar Evanna Lynch (who played Luna Lovegood) in 2021 for an episode and discussed the roundabout way they found out which part they were playing in the "Harry Potter" films.

The 'Harry Potter' production team seemed to make a last-second decision about the casting of Fred and George

On the podcast episode, Lynch asked if James or Oliver had a preference for which twin they played and how they ended up in their roles, and it turns out Molly Weasley wasn't the only one who couldn't tell Fred and George apart.

" ... We're talking five minutes before we're supposed to start, we still had no idea who was Fred and who was George," Oliver recalled.

He said when he asked casting director Janet Hirshenson who was playing each twin right before the first full-cast table read for "Sorcerer's Stone," she asked if he was "kidding."

According to Oliver, the casting director immediately went to author J.K. Rowling, producer David Heyman, and director Chris Columbus, and they had a "20-second discussion" before she returned to the twins and said James would be playing Fred and Oliver would be George.

"Now we always like to think they just ... 'Oh, you didn't get the memo about the huge meeting we had in Burbank with like 50 people on the call,'" Oliver said. "But in hindsight, it was probably either Chris, David, or J.K. Rowling just saying ... 'James is Fred.'"

He added, "That could be how it is. But we'll never know."

That split-second decision cemented their 'Harry Potter' fame with fans

Regardless of which Weasley they played — and how that decision was made — the Phelps brothers still have a solid fan following almost 20 years after first appearing in "Sorcerer's Stone."

During the podcast episode, both Lynch and the brothers shared how they keep on top of their fan mail.

After the Irish actress said she used to spend hours writing responses before her dad took over the operation. James and Oliver also admitted they had some help.

"James and I were very lucky, our granddad took up the mantle of that, like when it first started coming in," Oliver said, revealing that his grandfather had a strict regimen for getting them done. "... When he, unfortunately, passed away, his wife, my Nan, took up the mantle, and then she did it for years and years afterwards as well."

He continued to explain that after their grandmother died, he thought their fan mail kind of "lost the magic."

The Phelps' next "Normal Not Normal" episode, set to premiere this week, will be the second part of their interview with Lynch.

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