Paul Merton has been at the forefront of the UK improvisation scene across four decades.

Having appeared in the first ever episode of Whose Line is it Anyway? on Channel 4 in 1988, and as a founder member of the legendary Comedy Store Players, he went on to create Paul Merton’s Impro Chums who have starred at several Edinburgh Fringes and taken their adlibbing ways on tour across Britain to great acclaim.

The longstanding line-up of Paul, Mike McShane, Suki Webster, Richard Vranch and Lee Simpson, has been added to in the shape of keyboard player Kirsty Newton.

The group is for its latest national tour - which comes to the Wycombe Swan on April 23 and the Aylesbury Waterside on April 9.

What would you say are the main differences between putting together a written show and performing a show that’s entirely improvised?

Paul: The difference between this and a written show is that the latter takes a lot of pre-thought and hard work, and if you’ve got a bit that doesn’t work, you think “how am I going to fix that?” With impro, there are no bits to worry about because they don’t exist yet.

Do you watch any of the other impro groups that have cropped up in recent times?

Suki: I don’t watch masses but I do guest with lots: I love being invited to guest with all sorts of groups, it’s great fun. It’s good to work with other people and get new ideas. I think there was an increase initially because of the success of Whose Line…? and now with the success of Showstoppers and Austentatious, so other people think that this might be a path in.

Do you ever analyse what’s happened during an Impro Chums show or is it a case of once it’s done, you just forget about it?

Mike: We have a little post-mortem to talk about how something might have been more effective, but that’s about it.