By Fiona Pryor
Entertainment reporter, BBC News
US actor Henry Winkler, best known for playing The Fonz in sitcom Happy Days, is to star in one of Britain's enduring Christmas traditions, the pantomime.
Henry Winkler and Patrick Duffy have become TV icons
Winkler, 61, who made his name in the show three decades ago, is starring as Captain Hook in Peter Pan at London's New Wimbledon Theatre.
Patrick Duffy, who starred as Bobby Ewing in soap opera Dallas, is also donning a costume and tights.
The 57-year-old is appearing at the New Victoria Theatre in Woking as Baron Hardup in Cinderella.
Both actors admit they did not know what panto was when the job offers came their way.
Since then they have both had a crash course in understanding the meaning of the tradition.
"They're still explaining it to me. I've had a week of rehearsal, my brain is numb," Winkler says.
He stepped in after David Hasselhoff pulled out to appear as a judge in Simon Cowell's latest US talent show.
Winkler admits when he first got the call he imagined he would be working out of a box with a white face and not saying anything.
"I thought 'why would you do Peter Pan with no words?'"
Now Winkler understands what it is about and how important it is to the British public, making him proud to be involved.
"I'm honoured that I'm one of the first Americans to be chosen to be in this tradition since 1607," he says.
Winkler and Duffy think pantomime should be taken seriously
Duffy says he now understands what traditional pantomime is, comparing it to children's theatre because of audience participation.
"There are references that are topical and words that are not used anywhere on planet Earth except the UK and they'll be used for rehearsal and people will fall down laughing," he says.
"I'm looking around and they go over my head like a foreign language.
"So these are things as Americans that we don't even participate in. We let the local people enjoy the local people enjoying," he adds.
So what made the two American TV icons want to participate in pantomime?
Duffy jokes he accepted the part because of the "sparkly costumes", and thought it would be a fun assignment.
"I think that we are fortunate to be involved in one of the fun professions on the planet and this is one of the most fun aspects of the theatre experience," he says.
"So as long as I came here to enjoy myself - it's the perfect job for my personality."
Pantomime received a serious boost when Sir Ian McKellen - best-known for playing Shakespearean roles and Gandalf in Lord of the Rings - starred in panto at the Old Vic for two years running.
The 67-year-old stunned the theatre-going world in 2004 when he announced that playing Widow Twankey was one of his lifelong ambitions.
"You don't get much more serious than that," Duffy says.
Veteran TV actress Susan Hampshire will appear alongside Duffy as the fairy godmother, which he says made him eager to accept the challenge.
Playing Widow Twankey was McKellen's ambition
"I thought: 'If she's doing it and playing the same role second year in a row I want to go be a part of that.' I want to find out what that's all about - and I think it's wonderful," he explains.
Both Duffy and Winkler are adamant that pantomime should be taken seriously, no matter how light-hearted the show.
"If people actually say that panto is not an actual stage show it is because they have not done it. I'm not kidding. It seems to me to be very real, and very very fun," says Winkler.
Duffy says: "I think its always been taken seriously by the people who love it. It is a respected tradition in this country of holiday theatrical extravaganzas."
Peter Pan is at the New Wimbledon Theatre until 14 January. Cinderella is at Woking's New Victoria Theatre until 21 January.