The upcoming series, which is due to air next month, was filmed without a studio audience due to Covid-19, with an adapted format to adhere to the government guidelines around social distancing.

The contestants will still have the choice of four lifelines, but the Ask the Audience option will be replaced by another Phone a Friend, alongside the 50:50 and Ask The Host lifelines.

Host Jeremy Clarkson said: "Well, I'm absolutely thrilled and delighted that we've found someone who seems to know just about everything. I can't wait for the viewers to see it and I want to watch it back too. 

“I was just in awe of this contestant and think they are probably the best the show has ever had in its 22-year history. It was a joy to sit and watch it unfold.”

The successful contestant, who will remain anonymous until the episode airs, joins the small club of Millionaire jackpot winners. Only five contestants have walked home with the million-pound jackpot, not including the controversial winner Major Charles Ingram, whose cheating scandal was dramatised in ITV series Quiz.

The new five-part series of Who Wants to Be a Millionaire? will return to ITV in September.