With years of experience and an incredible talent providing the foundation to its shows, it is no surprise that The Showstoppers never ceases to prove itself as being at the forefront of improvised comedy. The premise of the show is simple: the director of a new hit musical has got Cameron Mackintosh on the phone and has his chance to make it big. The only snag? He hasn’t written the show yet. So with the help of audience suggestions (which they were joyfully willing to offer) he gets a setting, some musical styles that have have influenced the show and a title that screams ‘it’s a hit’.

And so we begin our journey into “Wonderground”, a musical about an enchanted tube station with influences ranging from Singin’ in the Rain to Grease, completely made up by the cast and the band as they perform it, literally on the spot. As the first chords are struck and the station attendant belts out his first bar of the Mamma Mia!-influenced opening number it feels like the perfected brainchild of a West End writer, and not the immediate imaginings of a group of performers. This is where the wonder in this show lies: the ability of the cast to invest in and commit to their characters and storyline so convincingly that it is often hard to believe it is being improvised.

The band of keyboard, percussion and saxophone (and for the closing number, surprise flamenco guitar) holds the show together almost seamlessly, changing between the audience-suggested musical styles with unmitigated ease at the whim of the director. Their pastiche of the ever-recognisable musical styles of West Side Story and Les Misérables provided particular comedic satisfaction for the musical theatre geeks in the audience, with the actors echoing the pitch-perfect parodies in their vocal styles and performances.

The true driving force of the show is the ensemble, who create a surprisingly complex narrative and an array of entertaining characters at the same speed as we are watching them. The locations move between Venice, New York, Canada and old London town with musical numbers ranging from a love-laced tango to a cockney romp between two best mates with the performers morphing and creating anew for every situation given or discovered. While some shows would lean on the improvisation as their main strength, the acting and vocal abilities of the entire ensemble are unflappable as well, creating something great every performance. It is magical to watch and almost impossible to believe. With a brand new and probably very different, surreal and entertaining show every night, catch this while you can. I will definitely be going again.

The Showstoppers are playing various dates and locations throughout the year. For tickets and more information, see The Showstoppers website.