Enormous sheets of plywood straddle the seats and a tangle of ladders stretch up into an array of high-slung lights, darkened at the moment, and giving the familiar interior of City Hall Theatre the appearance of a gloomy warehouse.

This, a Saturday morning just two weeks before the opening of Noel Gay's smash hit musical, `Me and My Girl', is the moment of truth for dozens of people who have been toiling for weeks now, to bring about that moment of theatrical magic when, accompanied by a swell of music from the orchestra pit, the curtain slowly rises on a street in Mayfair.

The `unsung heroes' who have given up yet another weekend to make this year's annual Gilbert & Sullivan Society musical a reality, number about a dozen -- mostly hefty male volunteers who stagger under the enormous weight and size of the various wooden contraptions being hauled inside. There is a moment of panic when a heavy shower of rain descends but (sighs of relief all round) all is well -- "the painted stuff was already moved in.'' Overall, it will take one week to get the set in place and in working order.

Peter Belton is making his debut as stage manager for this production and is in charge of the morning's activities, as all the scenery, painstakingly constructed by Richard Klesniks and crew from Peter Woodhouse's set designs, is finally brought into City Hall. He is remarkably calm.

"This is a huge set, one of the biggest we've ever had -- if not the biggest -- but I have every confidence it will fit together.'' Ignoring the hoots of laughter that greet this comment, he goes on, "if not, we have some carpenters on hand! But realistically, we can only test it when we get it all here.'' Peter Belton, who has `crewed' for countless G & S and BMDS productions, has also designed lighting for several shows, including the Bermuda Festival production of `Richard III'.

Mr. Klesniks, who teaches woodwork at Sandys Secondary School, became involved in theatre only last year, when he co-designed and constructed `Evita'. The bug has obviously bitten as, in between working on `Me and My Girl', he has also managed to head up the construction team for the recent BMDS production of `The Merry Wives of Windsor'.

Set and lighting designer, Peter Woodhouse is currently working on his Masters in Theatrical Design at the University of Southern California, for whom he has designed `West Side Story' and `Macbeth'. Involved with the theatre since his school days, he also designed two productions for the Edinburgh International Fringe Festival.

Producer Mrs. Marjorie Stanton, taking delivery of enormous boxes of pizzas to keep the stage crew fit and reasonably happy, says, "Nobody really realises what goes on when you mount a major musical production. The audience looks and thinks, `Oh, that set is wonderful!' but the average theatre-goer has no idea of who the designer is, or how he came up with a particular idea for a scene, let alone how it's been built. We have a wonderful team of volunteers and it never ceases to amaze me that people are prepared to devote so much time to making our shows look so professional. They must enjoy it, because so many come back, year after year!'' Without giving away any secrets, it can be revealed that the stage effects in `Me and My Girl' promise to be spectacular. As director Annette Hallett points out, there are four scene changes in the first musical number alone.

It is difficult to see, at this stage of the operation, just how this will all come about.

More than meets the eye for this musical Mr. Belton points to a huge wooden disk, which resembles a huge spinning wheel, one of two units, almost 12 feet in diameter and made of one-and-a-half inch plywood with 40 wheels on each, all set to rotate and thus produce five separate scenes out of each unit. This, it transpires, is called a `periaktoi', but was long ago fondly re-christened `pterodactyl'.

He indicates another pile of vast wooden shapes which will become a pair of double doors with Georgian columns and porchway, each door being too heavy to lift.

"The whole conception of this design is a realistic, 3-D effect, so in the library scene, for instance, all the `books' have been built with individual bits of wood and painted to look like books. And in the bar scene we have about 70 real bottles, filled with tea to look like booze.'' For Mr. Belton, the morning's work has been preceded by hours of telephoning, organising crews and heads of technical departments. He says he is grateful to the many people who donate such things as set furnishings, hair-styling services or, in the case of Mr. David Stanton, two donated trucks and drivers to transport the scenery from the Dallas Building where it was constructed.

Musing on that all-important opening number, Mrs. Hallett reveals that one of them involves a Bentley car. "We haven't quite figured out how we're going to manage this -- probably a cardboard cut-out, suitably painted, that will move sedately across the stage -- but we're sure we can achieve our goal.'' There is more laughter from the crew as she goes on to mention that costumes for the famous Cockney `Pearly King and Queen' and their retinue will require about 4,000 buttons to transform their outfits. "Tawnya White-Johnston is co-ordinating the costumes (most are being imported) but Gretta Petty is in charge of the buttons.'' Mrs. Hallett, who directed `The King and I' two years ago, says she chose this show out of two possible options. "I felt that `Me and My Girl' was best suited to this venue. It's light, humorous and a lot of fun, and because it's British and my own background is British, I thought I would have a better handle on it.'' Asked about her approach as director, she replies, "You have a group of very talented people who all have the same script as I have and they come to me with their concept of what that script is saying, and it's my job as director, to blend all of that into one unit. As I see it, my job is to use my knowledge of all the various areas to make it work. So far,'' she adds without quite crossing her fingers, "the problems have not been insurmountable! Until we bring all the elements of the show together, of course, it's not possible to say they've all been solved, either. The next two weeks will be really, really interesting!'' As co-ordinator of the show, both on and backstage, she feels it is important to be able to compromise, to have a flexible imagination, and problem-solving skills. "Losing your temper doesn't help -- although tempers do get frayed at times,'' she adds. "I sometimes feel my role is like that of a juggler, who gets 47 plates spinning all at once without dropping any. That's what my life is going to be like for the next two weeks.'' She has been working on the show since April, when she was first handed the script. "Of course, I read it, over and over, but I always like to talk to as many people as I possibly can who have seen it or have special experience in a particular area. It gradually takes your life over so that even if you don't actually sit down and study every word, you find that a good part of every day is spent thinking about the various problems. I personally feel it is very bad for a director to have too rigid a concept, because that kind of inflexibility is difficult for the other heads of departments. It's vital to take advantage of a new mind, a fresh pair of eyes! This is how I worked on `The King and I' and that was a very happy show, and I hope it works out the same for this. If the cast and crew are happy and take pride in what they are doing, I think you have a much better chance of coming up with a good show.'' Mrs. Hallett points out that `Me and My Girl' is a musical in the traditional sense of the word, rather than a musical play that has big numbers sprinkled throughout. "In this show, the main emphasis is on big, strong numbers with a story line that threads it all together. "So, although the acting is very important, it takes second place, on this occasion, I think, to the music and choreography.'' James Burn (who composed the original score for Warren Cabral's `Joan of Arc') is the gifted young musician who wields the baton as musical director, and Barbara Frith is the choreographer.

"The sheer exuberance of the musical numbers and the way in which Barbara has built the full essence of those huge numbers on a small stage is quite remarkable. All of her brilliance has gone into this work. Her wonderful, comedic timing and sense of staging produces such a sense of joie de vivre!'' Annette Hallett believes that the Bermuda Festival is largely responsible for the high degree of professionalism achieved by local theatre technicians. Her own husband, Bruce Hallett, perfected his talents through working with the Festival.

"He learnt a huge amount through working with people coming in from overseas.

And people like me and Beverly (Waddell), who is the lighting manager for the show, have also had the chance of learning so much by working alongside professional groups. I wonder if local theatre would be at the level it is now, technically, if it hadn't been for the Bermuda Festival.'' Ms Waddell is in charge of the running crew -- "the people who push the buttons on the night!'' Her interesting in lighting began years ago, when her late father, Leslie Waddell, worked on the special effects for Noel Coward's `Blithe Spirit' and she became his helper.

"At the moment,'' she says, "we're not sure that the onstage lights are going to fit in between the scenery, so that's the next problem we have to solve.'' Other important `departments' that form the intricate mosaic that makes up the whole show, are headed by Robin Gray, who is in charge of the all-important sound system, and Ian Burch who produces all those `special effects'. Kimerly Murray keeps track of all the stage properties, with Judy Rollin in make-up, and Chauncy, once again responsible for the hair-styles.

Out front, Diana Peers is organizing the Box Office, Freda Olivey becomes `front of house' manager, while Tim Taylor has designed the poster and programme cover.

The Gilbert & Sullivan production of `Me and My Girl' runs at City Hall from October 4-14. The large cast includes Richard Fell, Beverly Crick, Karen Musson, Keith Madeiros, Steve Parkinson and Kathryn Winter.

The Box Office opens on Monday, September 25 at the Visitors Service Bureau (295-1727), Monday to Friday from 10 a.m. to 4 p.m. Tickets are $20 and the curtain rises at 8 p.m. There will be a Matinee on Sunday, October 8 at 3 p.m.

Children will be admitted at $15 for the Matinee only. There will be a Champagne Reception in the City Hall Foyer following the first night performance.

SETTING UP THE SET -- One of the giant revolving wheels which will support the lavish stage designs for the Gilbert & Sullivan Society's production of `Me and My Girl', is carefully moved into the City Hall Theatre.