Anything Goes, Nowadays. You go to the theatre and you have to make up your own musical show. It’s wonderful, it’s marvellous... it flew us to the moon.

What is brilliant about Showstopper! The Improvised Musical is how the multi-talented cast can so lovingly send up all the different theatrical styles. Seeing pieces you adore mimicked with such tender attention to detail is hysterically funny because it is like laughing at yourself and everyone loves that.

There is no list of characters and players because the plot is decided on the spot but these are the six people I thought I saw playing multiple roles and they were all amazing. They are all impro experts: Ruth Bratt, Justin Brett, Pippa Evans, Adam Meggido, Philip Pellew and Lauren Shearing.

At the start, director Dylan Emery invites the audience to suggest the setting for the show, the musical styles and the title.

Last night (Wednesday, May 31) in Cambridge, we had a musical set at Addenbrooke’s Hospital, called You Have to Break it to Make It, in the styles of Chicago, Sondheim, Phantom of the Opera, Motown and Avenue Q. Thrown in was some stirring gospel singing and cleverest of all, a tasteful take-off of London Road.

(This is a stage show based entirely on interviews with people after the Suffolk killlngs. Neighbours of the dead women were interviewed and what they said was set to music. It works because themes are repeated poignantly and people finish each others sentences, as they do in real life, so unwittingly, their lines are musical.)

Last night, our lives were in their hands and they tickled us remorsely. We descended into helpless laughter for two hours of relentless parody. We had a musical medical drama with references to a vegan restaurant thrown in. (That had been another audience suggestion for the setting). A tall, attractive doctor (is there any other kind?) made stern-faced references during surgery to quiche removal. “It’s a Lorraine so it ought to be straightforward.”

Ruth Bratt is a comic genious, side-splitting from her opening line as the Irish attendant in the cafe, serving the doctor his coffee with a Renoir created in the foam “Oh YOU’VE had a long shift have you, I’ve been here since yesterday.”

She creates the noises for the coffee machine and the beeps in the operating theatre. This shouldn’t have been anything like as funny as it was and it is impossible to convey in writing. That goes for the rest of the show, you really had to be there and you should.

Ruth was delightful in her dance parodying Bob Fosse’s choreography for Chicago and priceless as a drunken teenager walking beside the Cam in a scene where the doctors go punting. Her characters are instantly recognisable.

Aware from the start that Jeremy Corbyn, Amanda Rudd and Tim Farron were slugging it out just over the road at Cambridge University’s Senate House for a live, televised election debate, the tone on stage was amusingly political.

The hospital porters’ gospel song about the living wage going up to £20 an hour brought the house down, “Thank the Lord, Heaven is a place we can afford”.

But then so did every other number, including one in the style of Avenue Q where the line is: “You have to do something you don’t like all your life or starve.”

At one point, Corbyn’s character came on stage to say gently that this overworked NHS isn’t the one he wants, he wanted everyone to be kinder to each other (if that wouldn’t upset anyone....) and Jeremy Hunt was described as “the man who put the N into cuts.”

The medics in the house loved it and so did the rest of us. It was for the many, not the few.