The quick-thinking comics of Whose Line is it Anyway - the TV improvisation show - are performing in Birmingham tonight. Tallest in the troupe is 6ft 6ins funnyman Stephen Frost. It was either stand-up or a career as a high-jumper, he told Jessica Shepherd.
Stephen Frost is swotting hard for his performance at Birmingham's Hippodrome Theatre tonight.
He has been watching soaps, B-movies, spaghetti westerns and black and white classics all day.
"You have to be very familiar with all the genres. The audience could suggest absolutely anything," he says.
For those unfamiliar with the format of Whose Line is it Anyway, comedians act out quirky scenarios shouted out by members of the audience in a particular film or theatre style.
Rounds include 'Who Am I' - a game where the audience give all the comics a profession except one, who is taken off stage. He or she then comes back and has to guess what it is.
In its heyday, the 30-minute TV show was as much part of Friday nights as a pre-weekend pint with colleagues.
It has featured some of Britain's modern comedy greats - Stephen Fry, Sandi Toksvig, Josie Laurence, and Paul Merton.
Merton will star in tonight's performance, called The Improvisers. He will be joined by Andy Smart, Jim Sweeney, Richard Vranch, Suki Webster and, of course, Frost.
The secret to improvisation comedy is to keep your mind empty, according to Frost.
"You have to just go in totally blank. It's rare not to have an idea immediately when something is shouted out. Too often you have too many.
"You surprise yourself with what you say and do. It's like an out-of-body experience. You look back and think 'did I just say that? Where the hell did that idea come from?'
"We don't have a secret code, we just have all been friends for 20 years and know the way we tick. One of the hardest things is to stifle your own laughter and giggles at your colleagues' performances.
"The rudest bits were edited out of the TV show."
Frost did Whose Line is it Anyway for five years between 1992 and 1997, between roles in Mr Bean, Just a Minute, Never Mind the Buzzcocks and Blackadder.
In that time he has been asked to mimic a pig in a monastery, a giant spider with a squint, and a chimpanzee on the way to Mars. All, of course, in the style of a silent movie or an American sitcom.
"There are two occasions when I sweat: before I go on stage and whenever I walk into a bank.
"But performing is all I can really do. I left school without any qualifications. I had a choice of a life as a basketball player, a high-jumper or a stand-up comic.
"Anyway if I'm desperate I can always waggle my bushy eyebrows. That always raises a laugh."
The 49-year-old, who lives with his wife and daughter in Dulwich, east London, started out on the comedy circuit aged 21 when he graduated from drama school in the capital.
"Back then I was considered 'alternative' because I didn't opt for cheap racist and sexist gags. British comedy goes in phases. At the moment it's a bit laddish, a bit loutish, and quite surreal.
"The stand-up scene, with many exceptions, is still pretty much the same as it was in the 1980s - full of single men talking about their 'girlfriends'," he says.
* The Improvisers starts at 7.30pm at The Hippodrome Theatre, Hurst Street, Birmingham. Tickets cost between #15.50 and #21.50. For more information or to book call 0870 730 1234. The performance is the first stop of a national tour which lasts until September 2005.