Charles takes to stage during tour of revamped Wilton's Music Hall
The Prince of Wales took a turn on the stage of the world's oldest surviving grand music hall as it was official re-opened after years of restoration work.
Like an old pro, Charles had the audience of Wilton's Music Hall in stitches when he said he was drawn to the attraction after his first visit in 2006 - "I'm afraid I'm rather a sucker for these sorts of projects."
Despite its then-dilapidated state, he became Wilton's patron and returned to see the results of the final restoration phase to safeguard the unique building opened in the 1850s by entrepreneur John Wilton.
At the time it was described as the "Handsomest Room in Town'' and had a sun-burner chandelier with 300 gas jets and 27,000 cut crystals in its mirrored hall.
The building has played host to may famous stars including Champagne Charlie, who played a key role in the 1889 Dockers Strike which resulted in the formation of the UK's first trade union, and it also acted as an evacuation centre during the two world wars.
Today it is the only intact survivor of the early grand music hall era and a precursor to the empires and palaces of the late 19th century. It reopened for regular productions in 1999 after restoration work had begun on the derelict site and it is once again a popular venue.
In a short speech, Charles told the audience who included impersonator Rory Bremner and lyricist Sir Tim Rice: "It's been a very special morning and I'm thrilled to have had the chance of meeting at least some of the people involved in putting all of this back together again.
"I know how difficult these projects can be and the frustration of trying to find the money and everything else."
Charles was joined by Camilla for the visit to see the final phase of work, costing £4.5 million, that sympathetically repaired the hall and 17th century houses that make up the front of the building while retaining its faded and weathered appearance.
In the famous hall, comic Barry Cryer performed with son Bob in what was dubbed the "Simon Callow Breakfast Show" by Charles after Callow had introduced acts from a bill that could have come from Wilton's heyday.
Barry Cryer joked afterwards: "We can boast we were in a royal variety show that was over very quickly. I bet Charles and Camilla were thinking, 'This is good, bang, bang, bang'."
Speaking about Wilton's, he added: "It's a hidden treasure that's the cliche, it's just magnificent this place. People can't believe it the first time they come and walk in and I couldn't the first time I came."
By the 1960s Wilton's had fallen out of use and was threatened with demolition by a London County Council proposed project to clear much of the area around it for development.
A campaign was launched to save the building led by theatre historian John Earl who persuaded the poet John Betjeman and the newly formed British Music Hall Society to back it. They were successful and the attraction in Wapping, London, was saved in the mid 1960s.
Comic Spike Milligan also worked to safeguard the building but it suffered more damage as it remained empty, and audiences would have to wait until 1997 to see a production - The Wasteland.
The attraction was finally put on a firmer footing with the formation of the Wilton's Music Hall Trust in 2004 and a major programme of works began eight years later to make all areas of the building safe and habitable.
Mr Earl, now aged 87, said he did not think he would see this day after first having walked into the building in 1963: "It's taken many many years for this to come about - my goodness - I've lived to see it.
"The great thing to me, I know the history of music halls, I know this place is important, I'd never walked into it before that time and it worked on me then and it still works on me.
"You walk through a dark hall, from a little alleyway, and you find yourself in an even darker corridor, then you open the door and there's this incredible room - it still works, I gasp every time I walk in."
Many of Wilton's walls remain unplastered, with much of the joinery like doorframes and skirting boards missing, creating a faded grandeur to the building.
Tim Ronalds, the architect who oversaw the restoration work, said: "If you plaster the walls, it just becomes an ordinary building. We had the principal 'do as little as possible', we didn't do anything that wasn't necessary - we wanted to keep the atmosphere."
Speaking about the significance of the building, he added: "During the 20 years from 1850-70, the time Wilton's Music Hall was open, that's when variety theatre was developing.
"It came out of places like Wilton's, they exported it around the world and X Factor has come from it."
When Charles and Camilla first arrived they were greeted by posey girl Clara Bierman, aged two, whose mother Kate is the attraction's development director.
They toured the building and met school children involved with theatre projects from learning music hall songs to making bunting decorations for the attraction.
The heir to the throne joined in with a rendition of Ta-ra-ra Boom-de-ay, a famous vaudeville song, when a group of school children began singing it.
Summing up the appeal of Wilton's, Simon Callow said: "In itself it's a beautiful, beautiful theatre, so any actor who walks into this place, and theatre maker who doesn't immediately want to do a show here must be dead - it's just thrilling."