"You've got to have a moustache. That's a must."

I'm discussing the definition of a cossack with Alexei Ignatov, spokesman for the Russian state dance troupe currently tearing up theatres across the country, the Stavropol Cossacks.

"You have to be very, very acrobatic and be highly trained with sabres, horses, singing, dancing. There's a lot to it."

Extending the maxim of never trust an Italian restaurant where the chef doesn't speak Italian, it's reassuring that none of the Russia-born troupe are available for an interview, as none of them speak English.

So authentic are they in fact, that one of them had a grandfather who was an original cossack - therefore employed in the days of the Tsar to protect the Russian borders against the Turks and whoever else fancied their chances.

Alexei explains what their eyeball-popping show, Cossack's Fiery Soul, is about: "It shows the journey through a cossack's life through singing and dancing, there's some spectacular fighting and acrobatics as well. It's part of Russian folklore.

"The whole idea was to present some Russian culture to as many people as possible," he explains. Hence why, instead of selling out a London venue every night for a month, Alexei is speaking from the auspicious surroundings of Doncaster. They have taken in the likes of France, Japan, Germany, Spain and US - where they sold out three 2,000-person capacity shows every day.

"So far the audiences have been just amazed by the shows; some people are sweating by the time they leave as it's so physical and there is so much energy behind it."

It's as much about brain as brawn, though. Troupe members have had to study cossack culture and history at higher education institutions for years, to achieve the "deep understanding" that is required.

If it all sounds rather heavy going, the show itself is exhilarating for the viewer, who gets treated to (literally) sparks flying during the titanium sabre fights, opulent costumes and even a vengeful woman pulling down the pants of an indecisive man during one song.

Alexei also carefully explains that the language difference between performer and viewer is no barrier. "Of course the songs are in Russian, but because of the level of performance, people will know exactly what they're talking about."

A unique spectacle, and probably unlike anything you'll ever see, given the dearth of similar groups hailing from Russia. Ideal for anyone, except those with pognophobia (fear of facial hair).

Cossack's Fiery Soul, Ashcroft Theatre Friday, November 10; call 020 8688 9291 or visit fairfield.co.uk for tickets.