After entering the house this evening, six housemates will be sent to a "basement pigsty" and will be forced to live without any luxuries and with minimal food for the opening days of the series.
With filth and cobwebs on the walls and filthy mattresses locked up in chains, the unlucky celebrities will have to deal with the worst conditions in the show's history.
The other six housemates will remain in the main house and will have as much food and alcohol as they like, access to a gym, a garden and a hot tub.
Basement housemates will be able to see what they're missing out on via a plasma screen.
A Big Brother rep told Digital Spy: "Its not going to be all champagne and air kisses as celebrity big brother kicks of this year. Some of the house mates will have to face a very different kind of house - the basement. It will divide them and test them like never before."
This year's Diary Room chair is designed to look like a block of carved ice with a fur throw over the top.
X Factor reject Rylan Clark, sports star Frankie Dettori and US reality TV duo Heidi Montag and Spencer Pratt are among the famous faces taking part this year.
Jim Davidson has been replaced as a housemate at the last minute, following his recent police arrest.
Celebrity Big Brother, which is hosted by Brian Dowling, starts tonight (January 3) at 9pm on Channel 5.
Celebrity Big Brother 2013 - Rumoured housemates