So, here I am, a regular theatregoer for the last 45 years or so, but I’d never seen a production of Gypsy (A Musical Fable) before. My only links to the show are having twice seen the wonderful Side By Side By Sondheim – once with the original cast in 1977 and once at the (relatively) recent revival at the Donmar – as two of Side by Side’s highlights are If Momma Was Married and You Gotta Get a Gimmick. My other link is just hearsay, as the Dowager Mrs Chrisparkle saw the show with Bernadette Peters as Rose on Broadway in 2003 on what was to be the Dowager’s final swansong abroad – and I remember she came back bubbling over with enthusiasm for it.

Gypsy is based on the memoirs of Gypsy Rose Lee, but if you don’t know the story – and let’s face it, it’s a bit historical now – you may well be surprised by the way the plot turns and develops. What seem to be minor roles assume unexpected significance later on and similarly major roles just fizzle out during the course of Rose’s lifetime. But it’s easy to fall foul of what one might term Rose Confusion. The Rose in question is in fact the mother of Gypsy Rose Lee, a determined, fearless, but tactless control freak who gains vicarious delight in pushing her two daughters into stardom, milking every cliché en route (maybe that explains the pantomime cow) and to hell with the artistry. Rose is at the centre of the show; she is like an unstoppable ten-ton truck hurtling down the freeway of life with the other characters representing any other traffic that inevitably have to give way in order to survive without ending up in A&E.

Originally produced in 1959, Gypsy reunited the successful West Side Story combo of Arthur Laurents (book), Stephen Sondheim (then aged 29 – lyrics) and Jerome Robbins (choreography). Unlike West Side Story, the composer was Jule Styne, (more showbizzy and less classical than Leonard Bernstein). Many commentators have described Gypsy as The Greatest American Musical Of All Time, but I don’t think I can hold with that opinion. Yes it’s got some wonderful songs, but you need more than that. There are some elements of repetition that drag it out just a little longer than it needs (primarily those cringily awful routines inflicted on Louise, June and the Newsboys) and one or two songs that dip into sentimentality – Little Lamb, for example, is really quite nauseating.

What it does do – brilliantly – is progress its storyline relentlessly as we follow Rose through her life. Every scene drives the story forward – you’ve even got Brechtian scrolling scene titles at the side of the stage defining what happens each step of the way. Just as in real life, people appear unexpectedly and make an impact on you at certain stages and then later on they move out of your life; so it is with Gypsy, with at least two significant roles only appearing for a limited time before they are heard of no more. This makes for a slightly unbalanced presentation – if you were hoping for some nice easy tie-ups of the loose threads to create a happy ending, think again. Real life isn’t always like that, and it’s the show’s grip on reality that gives it its really hard edge. When Louise finally, accidentally, falls into stardom of a completely unpredictable kind, the show switches axis, making a big stopover to examine Louise’s success story, whilst losing sight of Rose, its original driver. At that point you feel that the show is going to end on an anti-climax; the younger rises when the old doth fall, as King Lear’s Edmund would say. But Rose comes back with the electric finale number Rose’s Turn, firmly re-routing the show’s sat-nav back on to its original course and ultimate destination.

This is a hugely powerful show, given a stunning production by Jonathan Kent’s direction and Stephen Mear’s choreography. Everything about its appearance is perfect, from the sets (backstage theatre rooms, cramped apartments, ludicrously colourful scenes for the excesses of Baby June’s performances), to the costumes and lighting. Nicholas Skilbeck’s amazing orchestra is sensational. It’s hard to imagine how any of it could be staged better. But if ever a show relied on performances this is the one.

I don’t think I’ve ever seen a show dominated so completely by one performer as this. Not in a selfish, hogging-the-limelight sort of way, but in a genuinely extraordinary performance that lights up not only all of Chichester but all of Sussex too, I should imagine. Imelda Staunton’s Rose is simply breath-taking. She’s a little lady, but boy can she sing and her understanding of the role is immense. Not only is her Rose a showbiz mother from hell, she is near-demented in her pressing ambition for her children. Her tunnel vision only has room for stage success, and to hell with the personal consequences. When she sings Everything’s Coming up Roses, with its mind-bending metaphors of sunshine and Santa Claus, bright lights and lollipops, you can almost hear the synapses snap crackle and pop in her head, whilst Louise looks on aghast at what’s headed her way. For me it was one of those classic moments when a show-tune you know really well suddenly takes on its original context from its musical framework that you didn’t know, and thereby acquires a completely different meaning. I always thought of the song as being the ultimate in optimism and good fortune; I now realise it’s almost the total opposite.

Standing ovations are given far too frequently in my opinion, but this was one time when it was a no-brainer. As soon as Ms Staunton came on for her curtain call the packed Festival Theatre stood in one clean sweep as if we had been rehearsing it all afternoon. No looking around to see if anyone else was standing, no hesitation as to when you should stand – it was as though all the world’s Mexican waves had simultaneously arrived at the Festival Theatre.

We really enjoyed the performance by Kevin Whately as Herbie, although I confess I did not understand one word of his first two lines, as he audibly settled himself down somewhere halfway between Yonkers and Tyneside. Once he got into the swing of it, he was great, and there’s definitely something of the Jimmy Durante in his portrayal of the long-suffering Herbie. His not being a natural song-and-dance man actually stood him in good stead for his part in Together Wherever We Go, giving him some nice comic touches as an antidote to his vocal input. It’s a wonderful song about teamwork, with Ms Staunton and Mr Whately being joined by Lara Pulver as Louise, who grows her character in confidence throughout the second act into her amazing transformation as the striptease sensation Gypsy Rose Lee.

The whole cast are superb. Gemma Sutton is great as June, the daughter with (apparently) all the talent, pushed into prominence by her mother, irradiating glamour and showbiz panache. There are some very smart performances by Dan Burton as Tulsa, practising out his dance routine (sensationally well) whilst Louise watches on in besotted admiration, Natalie Woods as the sweetly enthusiastic Agnes, and Anita Louise Combe as the gutsy Tessie Tura who together with Louise Gold and Julie Legrand turn in a hilarious rendition of You Gotta Get a Gimmick which brings the house down. And you cannot forget the astonishing talent of the young performers who play Baby June and Baby Louise, plus all the very young newsboys – I believe we saw Georgia Pemberton play Baby June in our preview performance and she was simply extraordinary.

But there’s no question that the night belongs to Imelda Staunton. If you had the remotest doubt whether or not she was a star before, that question is most certainly answered now. Surely this must transfer to the West End?