Hamilton told friends he was on a yacht in the south of France
Veteran Hollywood actor George Hamilton and former glamour model Samantha Fox are among contestants in this year's I'm A Celebrity... Get Me Out of Here!
They will be joined in the Australian jungle by ex-EastEnder Lucy Benjamin, Strictly Come Dancing's Camilla Dallerup and TV chef Gino D'Acampo.
How Clean Is Your House? star Kim Woodburn is among other contestants.
Anthony McPartlin and Declan Donnelly will again present the ITV1 show, which returns on Sunday.
The line-up is completed by Hollyoaks actor Stuart Manning, Sabrina Washington - a former member of girl band Mis-Teeq alongside Alesha Dixon - and interior designers and partners Colin McAllister and Justin Ryan.
Former Dynasty star Hamilton, 70, said there was no chance he would "wuss out" of the show's bushtucker trials.
Lucy Benjamin follows in the footsteps of former EastEnders colleague Joe Swash
"There's an old saying that a coward dies a thousand times but if you're brave you only die once," he added.
"It's like when a fly hits the windscreen, it doesn't think anything. So if you hear a splat, that'll be me."
He said he had kept his jungle plans secret from his friends.
"None of my celebrity friends will be watching as they currently think I'm on a yacht in the South of France with a silk robe on and a glass of champagne in my hand, surrounded by beautiful women," he said.
Fox, meanwhile, said she had always seen herself "as a bit of a female Rambo".
"I'll jump out of a plane, no problem," said the 43-year-old. "What I am scared of is creepy, crawly, wriggly, horrible things."
She said she was glad she would be filmed "under the waterfall in my bikini".
"I'm a 43-year-old woman and everything's natural about me, which I'm really proud to say, and I just want to show women in their 40s that we can still look great."
Actress Benjamin, 39 - who played Lisa Fowler in EastEnders between 1998 to 2003 - said it would be the first time she had been away from her daughter Bessie, who will turn four while her mother is in the jungle.
"From the point of me leaving her and getting on that plane out there, that is going to be the worst part for me.
2002 - Tony Blackburn
2003 - Phil Tufnell
2004 - Kerry Katona
2005 - Joe Pasquale
2006 - Carol Thatcher
2007 - Matt Willis
2008 - Christopher Biggins
2009 - Joe Swash
"So, if I can deal with that and get through the other side when I land I'm going to have a great time and just say, 'I'm going to give it my best shot'."
This all the participants have chosen to raise money for the same charity, Malaria No More UK.
"I've travelled a lot and seen malaria first hand, like when I was in Kenya," Fox said.
"I've had friends who suffered really badly from malaria and it's so important that Brits educate themselves before they go away on holiday."
It has been reported that model Katie Price - who met ex-husband Peter Andre in the third series of the show in 2004 - is going to join contestants in the jungle.
An ITV spokeswoman said: "Katie Price's participation in I'm A Celebrity
Get Me Out Of Here! is speculation."
Last year's series was won by another former EastEnder, Joe Swash.
Tennis player Martina Navratilova finished in second place while Star Trek actor George Takei was third.