London (CNN) -- Something strange is going on in Britain. Some of the biggest TV stars of the 20th century are donning luscious wigs and scaring the wits out of children.
And Queen Elizabeth isn't in a position to stop them either -- she's guilty of joining in herself.
Overweight men are squeezing themselves into dresses, young women are prancing about on stage incessantly slapping their own thighs, and everywhere families are wildly screaming "He's behind you!"
It doesn't make any sense. But then, that's pantomime -- or "panto" as the British fondly refer to it -- a musical comedy unleashed across theaters every Christmas season and like nothing you've ever seen before.
Imagine your favorite childhood fairy tale -- "Peter Pan," "Cinderella," or "Robin Hood." Now subvert it with cross-dressing, topical references, audience participation, big song and dance routines, and you've pretty much got the idea.
Small stage, big names
But wait. What's this? Recently panto has been getting a celebrity makeover. Once the realm of local actors, now international stars are getting involved.
Henry Winkler, better known as "The Fonz," from TV show "Happy Days," and David Hasselhoff, better known as, er, "The Hoff," are wearing Renaissance wigs, badly drawn mustaches, and 45 kilograms of embroidered velvet as they bring to life one of the most infamous panto characters of all -- Hook.
"For me, there's no other part," said 68-year-old Winkler, who has been playing the Peter Pan villain since 2006, resurrecting him again at London's Richmond Theater this year.
"All of a sudden you just hear the tiniest voice on the planet either yelling 'Booooo' or 'Peter! He's behind yoooouuu.' Then when Peter is banishing me from Neverland you hear this voice go 'Yay!' and I turn to where it's coming from and say 'Well, I didn't like you much either.' It's just great."
And it's true, one of the great joys of panto is seeing the audience erupt with lines that have been passed down through generations; youngsters standing on their seats to yell "Oh yes he is!" while parents laugh at the sexual innuendo flying just above their heads.
"It's not the kind of theater-going experience where you have to sit still and shut up and feel that you have to be very educated to understand," said professor Katherine Newey, chair in theater history at the University of Exeter.
"I think one of the joys of seeing it with children is that you've got an excuse to be a child again."
Not even Queen Elizabeth is immune to the magic of panto, with a treasure trove of old photos recently revealing she wore her own curly wig when she played the male lead of Prince Florizel in a palace production of "Cinderella" in 1941.
Swimming in lace ruffles and silk knickerbockers, the then-15-year-old Elizabeth starred opposite her 11-year-old sister Margaret -- who took the title role.
"It's the one opportunity for us to let our hair down," said Newey. "It seems like this weird, eccentrically British thing -- so of course we keep doing it because part of our national self-image is taking delight in being a bit odd and eccentric.
"Yes, the pantomime dame is a man dressed as a woman. Yes, the princip boy, the hero, that's a woman dressed up in tights and knee-high boots, slapping her thigh. Obviously."
And then there's the larger-than-life villain. Enter The Fonz.
"Everyone who is 35-and-up recognizes me from 'Happy Days,' said Winkler, today a grandfather-of-three.
"And they can call me The Fonz all they want because they have also gone with me on my journey -- I've never been restricted in my career by it," adds the man who tells me that over his career he's produced 19 years of TV series if you watched them back-to-back, and in 2011 received an Order of the British Empire for his work with dyslexic children after also suffering from the condition.
The native New Yorker admits he never heard of panto before getting involved. But now he's, ahem, hooked.
"It's the story of Peter Pan with Vaudeville in the middle -- it's like chocolate candy with this delicious melted syrup in the center," said Winkler.
"As Hook, I'm wearing about 100 pounds of velvet, I'm wearing a King James wig with curls down to my shoulders, I'm wearing a hat. If you don't make that animated, you will get swallowed up and then I would just be lost. So the movement is very calculated. It's a very important part of bringing the character to life."
Today, panto is seen as a uniquely Christmas tradition, but it wasn't always the case.
"Pantomime as we know it now really emerges in the second half of the 19th century," said Newey.
"The original pantomimes had an opening scene, generally a fairy tale, with characters which wore these big masks and were often quite satirical of contemporary politics or events."
When Victorian writer Charles Dickens began writing about Christmas and pantomime, the two became cemented in the national psyche, with panto even spreading to other Commonwealth nations. And with many Britons having Boxing Day -- December 26 -- off work, it became an ideal time of year to enjoy the show.
With The Fonz and The Hoff now tackling panto, does that finally make it cool?
"I never knew it wasn't," says Winkler.