I AM no thespian. Sitting safely in the stalls scribbling reviews is where you normally find me.

So imagine my excitement when an invitation arrived asking if I would like to join the cast of Spamalot!

The West End show that is “lovingly ripped off” from the classic film comedy Monty Python and the Holy Grail is on a UK tour that has had audiences in stitches all week in Southampton.

With comedy legend Joe Pasquale back in the role of King Arthur alongside Todd Carty as Patsy this is a seriously good show.

Well, quicker than you can say: “What, the curtains?”

I responded with a: “Yes, just tell me when!”

I was told to arrive at the Mayflower Theatre’s stage door at 6.30pm with just a pair of black boots. I was intrigued.

Was I to be a glamorous assistant to the Lady of the Lake, a vision in aqua and flowing chiffon, or maybe one of those spangled show girls all shimmering in sequins and silk?

Company manager Phil Sykes greeted me warmly and asked me if I was ready. “As ready as I’ll ever be,” I said.

Daily Echo:

Todd Carty, left, during rehearsals

He led me downstairs for my costume ‘fitting’ ahead of a planned rehearsal. I entered the quarters of wardrobe master Iwan Harries.

The room housed several washing machines and driers and our conversation was interrupted by his assistant, who held up a pair of boxer shorts and asked: “Are these Todd’s?”

“Yes,” he replied, clearly well acquainted with his company’s smalls.

He produced a key that unlocked a padlock on a kind of wardrobe/crate on wheels containing all the understudy costumes.

As I rummaged through the silky fabrics it felt like I’d been given access to the most exciting dressing up box filled with the unmistakable costumes of all those iconic Python characters. How exciting!

“So which one is mine?” I asked.

In the corner of my eye I spotted it.

Iwan was holding up what looked like a potato sack: yes, I was to be sensation in sack cloth as befitting my peasant role as The Hay Baler.

As I pulled this ample creation over my head sending my hair into a frenzy of frizzled static I really was good to go. No fancy make-over needed here.

Daily Echo:

Hilary with Spamalot stars Joe Pasquale, left, and Todd Carty

Phil reappeared and led me to the stage for a rehearsal and explained my part: there would be a montage of King Arthur and the knights travelling around the world and while this was happening the Hay Baler (that’s me) would slide on stage carrying a bale of hay and just stand there looking bored.

Then a cast member comes on with a Russian flag and Arthur and his knights perform a Russian Cossack dance and as they are dancing they are all shouting “Hey! Hey! Hey!”

But to finish they all shout “Hay!” and point at the Hay Baler and the bale of hay. The Hay Baler looks embarrassed and slides off stage again.

Some yellow sticky tape on the stage was strategically place so that I would know exactly where to stand.

I lifted the hay bale and discovered it was remarkably light; made of polystyrene and raffia.

The cast had already done a matinee performance earlier on but they had cut their break short so that they could run through my scene with me.

Joe Pasquale was first to arrive on stage and welcomed me on board, swiftly “complimenting” me on my costume.

“It matches your hair!" he said.

Hmm, hair that goes well with sack cloth and a hay bale... lovely!

Todd Carty was equally friendly and together with some of the knights they gathered round to re-enact my scene.

Todd clacking his coconuts in time with Joe’s imaginary horse, they galloped around the stage all for my benefit, the band striking up the tune. It went completely to plan but they agreed to do it again as it was such fun.

All smiles, Joe said to me: “It’s better than working for a living!”

After some chit-chat with Todd about the quality of the continental breakfast at the nearby budget hotel they frequent they both wished me luck and told me to just enjoy myself.

Then, moments before the start, Joe led me up to the curtain and said “listen to that”.

The buzz of excitement and anticipation on the other side of the drapes was almost tangible. I suddenly felt very honoured to be a part of this legendary show.

I settled in the wings and watched all the potty Python action unfold on stage. From the Finnish dancers slapping each other around the face with wet fish to the “Not Dead Yet” plague-ridden soul, who gets repeatedly bashed on the head with a hard shovel, it was so silly and so funny.

When cast members were singing and dancing on stage, those off-stage were skipping around singing, too. This was infectious fun that no one could resist. Everyone clearly loved what they were doing.

“We are all fools,” Joe told me.

Rapid costume changes and adjustments took place in the dark as the relatively small cast took on multiple roles. Stage hands hovered ready to wheel the scenery and props on and off.

Daily Echo:

Head of wardrobe Iwan Harries helps Hilary into her costume

Company manager Phil, whose job is to be “the eyes and ears of the producer”and make sure everything happens, appeared as my spot approached.

“This is one of the funniest bits of the show,” he said. “You are guaranteed a laugh.”

Crikey! I hope I don’t mess up then, I thought.

And so, as Andy Warhol said: “Everyone will have their 15 minutes of fame”.

I got mine. It may have been seconds, rather than minutes, but I took my cue, stepped out as instructed, gazed out beyond the blinding stage lights to the dark theatre seats and at the point the cast yelled “Hay!” and the music stopped I turned and gave them a bemused look and swiftly took my exit.

I could hear the audience erupt in laughter.

My acted deadpan face became a huge smile once back in the wings and my heart raced as I experienced the real buzz that comes from an audience’s laughter.

Wow! What fun!