Comedy lovers were in for a treat when Paul Merton turned up as a guest performer at the Corn Exchange.

His dry humour and quick wit fitted in with the Whose Line Is It Anyway style show performed by the Comedy Store Players.

The entire show was based on improvisation inspired by audience suggestion, including one particularly heavy heckler who appeared to have some form of Tourette's and couldn't stop shouting "Porn!"

His condition was in danger of spreading throughout the audience until it was quipped in the bud by the quick-thinking improvisos.

With regular Comedy Store performances in London and Manchester, the group are clearly used to hecklers.

The show faltered only slightly upon Merton's appearance but his dry, often surreal humour was swiftly incorporated into the fast-moving show - though not without a couple of ego tussles along the way.

The group, which included Richard Vranch, Andy Smart, Lee Simpson, Suki Webster and Steve Steen, kept the audience laughing out loud and the clap-o-meter off the scale to the end of the show and beyond.