How Harry Potter Ended Up Casting An Actor In Their 30s As A 14-Year-Old Girl

The "Harry Potter" universe is full of wild magical characters, from creatures to ghosts to evil wizards, and in the film franchise, Daniel Radcliffe deals with pretty much all of them as the titular Boy Who Lived. So what about the curious case of "Moaning Myrtle," the ghost of a teenage girl who haunts the U-bend of one particular toilet in one particular girls' bathroom at Hogwarts School of Witchcraft and Wizardry?

The ghost in question is played by Scottish actress Shirley Henderson in the second film, "Harry Potter and the Chamber of Secrets," and the fourth movie, "Harry Potter and the Goblet of Fire." Henderson, who was born in November 1965, was 37 years old when they filmed "Chamber of Secrets" in 2002, and that's ... kind of weird, right? In an archived article by Radio Times, Henderson explained how she ended up snagging this role — and that she didn't know anything about the original books before she auditioned.

"I didn't know who Harry Potter was," Henderson told the outlet before saying that her sister had read the books and was staying with her at the time. "Still, I wasn't convinced I could play a 14-year-old girl because I was in my 30s at the time," she continued. "But I spoke to the casting director Karen Lindsay-Stewart, and she said, 'I haven't told them your age.'"

That's when Henderson did, frankly, the funniest thing possible. "So I went to the audition dressed as a schoolgirl — white shirt, black skirt, ponytail — thinking, 'This is ridiculous.' I did my wee bit for them, and they thanked me," Henderson revealed. "Months went by, and I thought that was it, but then they phoned my agent, asked to see me again, and offered me the part."

In that same interview, when asked how she managed to pretend to be a little kid, Shirley Henderson summed it up thusly: "Myrtle is an old person in a young person's body, and because she's ghostly, there's a kind of mistiness. You're not looking closely at my face, so we could get away with it." Henderson is exactly right, in my opinion — because it's honestly sort of funny, to me, that a much older woman is playing the ghost of a particularly petulant teenager.

As for Myrtle herself — whose name was hilariously revealed as Myrtle Elizabeth Warren by series author Joanne "J.K." Rowling, bringing to mind a United States Senator of almost exactly the same name — she was killed, during her time at Hogwarts years before Harry and his friends ever arrived, by a basilisk roaming the school. I'll back up. 50 years before Harry's second year (the one depicted in "Chamber of Secrets"), Myrtle is a student at Hogwarts when a young Tom Riddle, the man who grows up to be Voldemort (Ralph Fiennes), unleashes a basilisk into the school by opening the titular Chamber. (Tom can do so as an heir of Salazar Slytherin, one of the Hogwarts founders, who was famous for being a Parseltongue — meaning that he can speak to snakes, including the basilisk.) 

If you're unfamiliar with basilisks from mythology, they can kill with a single glance, which is what happens to Myrtle; because the entrance to the Chamber is in a bathroom that she happens to be using when it shows up and makes eye contact, she then haunts that bathroom and becomes a key part of the mystery by the time Harry needs to solve it at Hogwarts.

You know what I find funny? The "Harry Potter" movies are not the only films that feature Shirley Henderson weeping profusely in the bathroom. In 2001, before "Harry Potter and the Chamber of Secrets," Henderson appeared as Jude in "Bridget Jones's Diary" alongside Renée Zellweger as the titular Bridget, and how is Jude — one of Bridget's besties — introduced? She's crying in the bathroom over her, as Bridget describes him, "f***wit boyfriend" because he doesn't want to go with her on a "mini-break in Paris." Jude does a lot more than cry throughout the "Bridget Jones" movies — she appeared in all three sequels, "Bridget Jones: The Edge of Reason," "Bridget Jones's Baby," and the 2025 Peacock hit "Bridget Jones: Mad About the Boy" — but it's really, really amusing that both of these characters are introduced as prolific bathroom criers.

Aside from her bathroom sobbing, Henderson has appeared in a lot of movies and TV shows, including "Trainspotting" and its 2017 sequel "T2 Trainspotting" as Gail, Bong Joon-ho's "Okja" as Jennifer, and the recent British crime thriller "Dept. Q" as Claire Marsh. Even if Henderson doesn't look familiar to you, she might sound familiar; not only did she lend her voice to "The Mandalorian," but she also voiced Babu Frik in 2019's "The Rise of Skywalker."

As for the "Harry Potter" movies, they're available to stream on Peacock and HBO Max now.