Chris Tarrant will oversee the celebrity special, which will feature David Hasselhoff and Denise Welch teaming up in full panto fancy dress to raise cash for their respective charities.
"One minute I'm terrified, the next I can't wait to jump into the seat. I've been gearing up and I'm ready to face the million pound question," said Hasselhoff.
"I'm playing for Pengeulan Primary School in Wales, a school close to my heart, I just hope I can win some big bucks for them."
Other celebs taking part are Tim Vine and ex-EastEnders star Cheryl Fergison, who are raising money for The Cure Parkinson's Trust and hospice at home charity ChYps.
Comic Vine joked: "I'm looking forward to appearing on the show very much. My previous best was one thousand pounds so I'd be happy if the show was called Who Wants To Win More Than A Thousand Pounds?"
The final couple are soap actor John Partridge and Big Brother's Alison Hammond.
"I'm really excited about Who Wants To Be A Millionaire? I've downloaded the app on my iPhone but can't get past £8k," said Hammond.
"However, when I met John Partridge I felt we were a match made in heaven."
Who Wants To Be A Millionaire? Pantomime Special will air on Sunday, December 9 at 6.40pm on ITV1.