Showstopper! The Improvised Musical

The Showstoppers present a show that is entirely improvised: a brand new musical is created at every performance, with hilarious results.

http://www.showstopperthemusical.com/

"Glorious... Showstopper! simply shouldn't stop." The Observer
"The show makes your jaw drop in impressed amazement
and your ribs ache with laughter." ***** Mail On Sunday 
"A professionally staged and brilliantly executed piece of work that is
a shining example of how good improv can be." ***** Chortle