judge joined for a special celebrity edition of However, viewers were astonished that the dancer-turned- judge made a huge error during a question about his specialist subject - dance and musical theatre.

The 58-year-old, who was on the show to raise money for a cause close to his heart, The Sick Children's Trust, kindly vowed to pay out of his own private funds if he got the question wrong. Little did he know that he would end up blundering seconds later - right at the moment that £32,000 was at stake. Anton was asked: "Which Tony-Award winning musical features a mash-up called Elephant Love Medley?"

The options were A) Hairspray, B) Moulin Rouge, C) The Book Of Mormon, and D) Six - and a cringing Anton was totally stumped.He decided to use his 50/50 lifeline, but was still left stuck after two answers had been removed, and vowed: "If I get this wrong, I'm going to give the charity £15,000 of my own money."

As the audience watched with baited breath, he chose the Book Of Mormon - and was sent to a humiliating defeat. He plummetted back down to £1,000, leaving him facing the prospect of supplementing his donation with £15,000 out of his own pocket.

Jeremy revealed the correct answer was Moulin Rouge - and, knowing the nation would have expected him to get a dance and musica theatre question correct, the embarrassed Strictly judge quipped: "Wait until I tell my wife!"

Meanwhile, Million Pound Menu star Fred Sirieix took his turn in the hot seat after Anton had been defeated, and at first viewers wondered whether his efforts would end the same way.

After all, he'd stumbled on the very first question, and used a 50/50 life-line to help him decide on a "method for staying afloat in a swimming pool".

Agonising over whether the answer was "treading water" or "passing water", he eventually chose the former - and was correct. His winning streak continued, as the Frenchman correctly determined that the Latin term meaning "for the public good" was "pro bono" - and eventually he won a whopping £64,000 for charity.

He donated proceeds to his own charity, The Right Course, which aims to rehabilitate prisoners by preparing them for fulfilling roles in the hospitality industry on release.