Ushers: The Front of House Musical is predicated on the frankly dubious claim that "it is guaranteed that there is more drama in front of the stage than on it." It would be a truly woeful play when you found yourself more engrossed with the waistcoated usher loitering by the door, scanning the audience for sneaky photography and mobile phone usage. The combination of this and that excruciating title (my plus one suggests the alternative West End Story) doesn't do Ushers any favours, so I'm pleased to be able to report that it is really much, much better than it sounds.

The Hope Theatre is a welcoming and effective space above the Hope and Anchor pub, though it must be said, not very well sound-insulated from both the pub and the busy road outside. This is less of a problem in the exuberant Ushers than it might be in other plays, though. Accompanied only by a pianist tucked into one corner, the cast are all talented singers, and particularly in the Les Mis-style Act One finale, in which five or six different tunes are layered over one another, they prove equal to Koutsakos' fun, melodic score.

The story unfolds in real time, set in the West End theatre about to open with – in a clear dig at last year's most critically savaged show, Viva Forever – Oops I Did it Again, the musical about the life of Britney Spears, starring Michael Ball as Britney's mum (because, of course). Theatre manager Robin is a bombastic tyrant and failed opera singer, ruling his team of young ushers with an iron fist and a furious commitment to hiking up the Spend Per Head. Somehow, in a fairly zippy 90 minutes, the show squeezes in a genuinely moving account of the relationship between struggling actors Gary and Ben, a tongue-in-cheek romance between new girl Lucy and future "Leading Man" Stephen, and a last minute, extremely satisfying coup d'état.

All this goes on in the background of some very well-observed, hilarious satire. Showing her the ropes, one character explains to Lucy: "these are the premium seats. That means that people pay £127.50 for the privilege of seeing some of the stage." One number introduces her to the different types of audience member she is likely to encounter: Americans ("do you have a playbill?"), critics ("oh, how ghastly") and middle-class Londoners ("is your popcorn organic?"). The interludes in which Robin explains the golden rules of "Making Theatre Better" are a little bit cumbersome, and even more so the heavy-handed attempt at profundity via apposite dictionary definitions, but they are an opportunity for some jokes at the expense of some current West End fixtures. Explaining that "run" means the length of time that a show is on for, Robin informs us that Theatre Nation's longest running show is La Melancholie, while their most recent is From Here to April. Ouch. My favourite, though, is the advice Lucy's mum gave her for a life in theatre: "Treat everyone as if they're Andrew Lloyd Webber." Besides the dialogue references, the music also weaves in a few allusions to well-known tunes from Les Mis, Phantom, Evita and the like.

It's not perfect – there was the odd line stumble on press night, and the blocking is a bit silly, frequently obliging off-stage actors to perch precariously and very visibly in the audience. Sometimes the dialogue is a bit clunky, and it's a shame that both the female characters are such complete airheads ("what's spend per head?" asks Lucy winsomely, because she is from Devon and has never seen a cash register before in her life). It is, however, consistently funny, musically inventive and even manages some pathos in the delicate relationship between Gary and Ben. So, while I would usually dispute the claim that ushers are the most interesting people in the theatre business, I might make an exception for those at the Hope Theatre. 

Ushers, at The Hope Theatre

The brand new Hope Theatre is hosting the world premiere of Yiannis Koutsakos and James Oban's first show. The idea of putting ushers in the spotlight is either brilliant or dreadful, depending on your point of view, but here it works startlingly well, combining deliciously bitchy satire with some catchy songs and likeable characters.