There’s nothing quite like a meticulously rehearsed improvised show to get people asking – nay, begging – for more. Take the deservedly popular Showstopper! as an example. It has that pleasantly old-fashioned air of a couple of brighter-than-usual undergraduates chatting up the audience and apparently canvassing its members over what sort of show they most appreciate seeing. All very laid-back and ad-hoc? Don’t believe a word of it!

Gradually the outline of the story of this new musical takes place, precipitated by a telephone conversation between Dylan Emery as the writer-composer and a certain high-powered producer (first name Cameron). Cameron has, very sensibly, turned down Emery’s plan for a show set on a racecourse; it is now time for the audience to make its own suggestions. What’s in the news? Well, cruise ships seem to be in trouble at the moment and it is, of course, the centenary of the sinking of the Titanic.

So our cast of five, smart in black with scarlet accessories, find themselves on the cruise liner La Traviata – we escaped The Flying Dutchman by a whisker – early in the 20th century. There’s a couple of hoodlums, their boss, his up-market wife and slightly more down-market niece, two sailors (one lovesick) and inter-locking plot strands galore. Hard-working musical director Duncan Walsh Atkins shifts us through mountainous seas of extremely clever pastiche – everything from Salad Days through Les Misérables to Avenue Q.

Ruth Bratt and Lucy Trodd are our two heroines, wooed by Adam Meggido and Nigel Pilkington with Phil Pellew as support. They all sing, dance, over-act and flip from one character (not to mention sex) to another in the blink of an eye, the doff of a cap and the twirl of a stick. It’s ideal Saturday night entertainment, and it’s almost certainly just as enjoyable any other night of the week.