Britain's Duchess of Cornwall visited the set of a celebrity TV talent show yesterday (25.11.11).

Camilla was invited by `Strictly Come Dancing' judge Craig Revel Horwood to watch final rehearsals for this weekend's show - the British equivalent of `Dancing With the Stars' - at the BBC studios in west London in order to give the remaining competitors "a boost".

A source told the Daily Mirror newspaper: "The visit was top secret but Craig thought it would give the remaining contestants and the crew a real boost if Camilla came down to watch them in action.

"The duchess is a big fan of the series and watches the show with her husband Prince Charles so she was very knowledgeable when she was watching the run through.

"None of the contestants could believe it when she walked in, but it certainly made them concentrate even more in the rehearsals and a few of the dancers seemed a bit starstruck."

Camilla and Craig struck up a friendship working on a variety of charity projects together and the judge was delighted his pal could make it to the rehearsals.

He said: "I'm delighted to have welcomed the duchess to `Strictly Come Dancing'. Having got to know her through our charity work and having learnt what a fan of the series she is, it has been a pleasure to show her a sneak preview of this Saturday's show and some of the work which goes into making the series."

In 2009, Craig even gave Camilla a dance lesson when they visited a London school on World Osteoporosis Day.

He said afterwards: "I'd give her 10. She kept rhythm, her timing was excellent, her footwork was excellent - she has the personality for it."