It may be difficult to believe a theatre and music troupe who have dominated the Edinburgh Fringe for the past six years with their ad-libbed performances will play in a school theatre this summer. 

Nonetheless, Hampton School’s 400-seat theatre hosts professional improvisers Showstoppers, as the school opens up the space to the community.

The group create a unique theatre experience through audience participation and improvise an entire musical from scratch.

“Every performance is completely different,” says Philip Pellew, a performer with the troupe.

The group uses a narrator who coaxes the audience into putting forward ideas for the musical - then the actors have their time to shine.

Philip says: “You can’t rehearse the show because it is completely unexpected.

“Like a football team you can rehearse the skills that you think you might need during the night.

“At the same time during the performance you’ll let people who are having a good night shine.

“It’s like if Ronaldo was having a particularly good game you’d keep passing him the ball.”

During the made-up musical the audience invents everything from the title and location to the music style, giving them a once-in-a-lifetime show that will never be repeated again.

Philip says: “People have said to us afterwards that they can’t believed we improvised it.

“When you go to the theatre you sit there and you know what’s going to happen and you just play the part of the audience.

“With this you are as much a part of the show as we are and it is something that we all created together, which is tremendous.”

Since its inception in 2008 the group, made up of 14 interchangeable performers, have created 500 off-the-cuff musicals.

The show is the currently at the Udderbelly Festival , had four sell-out West End shows and a Radio 4 series to its name.

Philip says: “It’s not like theatre it’s totally different.

“The improvisational performance is so exciting and great for younger people and people who don’t go to the theatre so much because you feel really involved in what’s happening in front of you.

“We ask you to imagine with us and as a result you have a much greater connection with it.”

Showstoppers; Hampton School Theatre; June 13; 7.30pm; £5 and £10; or 020 8783 4026; Free parking.