Finally catching up with Urinetown on its penultimate outing – the ‘muck-up matinee’, it felt more like attending a rock concert than a musical. The diverse audience, including a large youth element, gave several massive ovations to a show that seems to have become a cult hit in its limited London run at the St James Theatre. Director Jamie Lloyd’s production of this unique show, the original production of which enjoyed a three-year run on Broadway some years ago, is tipped to transfer as part of his Trafalgar Transformed season in the West End too. And judging from the reception of the audience on Saturday, it is a production that has more than endeared itself to its target audience.

Urinetown is the musical that has succeeded against all odds – mainly, I suspect, because it is a delicious satire that never takes itself too seriously and that pokes gentle fun at the very genre that it belongs to. Set in the future, in a drought-ridden city, the story focuses on business tycoon Caldwell B. Cladwell (the deliciously villainous Simon Paisley Day) who has monopolised public toilets (there are no private loos here!), charging a fortune for their use. Cladwell is helped in his villainy by a brutal police force led by a sleazy Jonathan Slinger as Officer Lockstock who narrates the story to the audience throughout, sending up the concept and material and even revealing what’s about to occur ahead of the action. Central to the plot are Jenna Russell’s beautifully drawn and wittily played Penelope Pennywise, who is the keeper of Public Amenity #9 and her handsome young assistant Bobby Strong – Richard Fleeshman in a career-defining role as an earnest and sincere hero whose father is sent to the dreaded Urinetown early on in the story for failing to pay to pee. Where this place is, if it even exists, gradually becomes clear – remember, Rodgers and Hammerstein this ain’t.

One of Urinetown’s many strengths is that it is a completely original musical, conceived by writer Greg Kotis after encountering a pay-per-use toilet while travelling through Europe. Mark Hollmann’s music (both Kotis and Hollmann wrote lyrics), is as diverse and witty as Kotis’ book – the songs here sit perfectly within the context of the show rather than being designed to have a life outside of it, like some of the shows it satirizes. Highlights include the opening title number where Slinger’s Lockstock explains the conceit of the story, Russell’s explanation to the poor that ‘It’s a Privilege to Pee’ and Fleeshman’s ‘Run, Freedom, Run’ which received a several-minute ovation with the company freeze-framed with their arms in the air, unable to move. This production is also blessed with a two-level set and design (bravo, Soutra Gilmour!) that are as perfect for it as the intimate space of St James Theatre, drawing the audience even further into the dark recesses of the story. The whole company – often in multiple roles – are clearly in their element, giving an excitingly energetic performance throughout. There are no weak links in a perfectly cast ensemble, and Karis Jack’s Little Sally (the recipient of Lockstock’s commentary), Rosanna Hyland’s love-interest Hope, Adam Pearce’s wicked Officer Barrel, Julie Jupp and Cory English are standouts in an exciting array of supporting characters.

Imagine trying to sell the idea of Urinetown on paper to a producer. The fact that this show – and this superbly-judged production – work so well is testament to the talent and imagination of writers Kotis and Hollmann, and of Jamie Lloyd and his cast and creatives who keep the whole thing moving at a fast and furious pace. However, the concept of the drought-ridden city where Urinetown is set and the serious environmental undertone of the piece, and its final twist as to who is really evil after all, are not so far removed from reality. As I arrived back at Paddington station after seeing the most original and witty musical that London has seen in years, I reached into my pocket for some loose change to pay the 30p toilet fee there. As the strapline for Urinetown says, ‘a drop of hope can change the world’.