Reality TV show Big Brother's opening show has attracted nearly seven million viewers - Channel 4's highest ratings so far for 2003.
Justine wants to have "as much fun as possible"
The fourth series of the show, which has previously been both a ratings and media hit, peaked at eight million viewers on Friday.
It kicked off with producers picking younger contestants than in previous years for the surveillance gameshow.
Recent series have seen older contestants struggling to get on with their younger counterparts - so producers have opted for a more youthful selection of housemates this year.
BIG BROTHER OPENING SHOW RATINGS
2000: 3.6 million
2001: 3.5 million
2002: 5.9 million
2003: 6.9 million
The 12 housemates are all aged between 20 and 32 - and include a fish trader, shop assistant and fashion designer.
They will be filmed 24 hours a day and must nominate who they would like to see voted off the show each week, with the TV viewers making the final decision.
The last person remaining in the house will win a £70,000 prize.
But the housemates faced an early test on Friday evening - deciding that four of their number should face the public's eviction vote one week before it actually takes place.
WHO WILL WIN?
14/1 any other
Until the 12 were driven to the house at Elstree studios, Borehamwood, Hertfordshire, they had never met before.
First to enter the house was 20-year-old Manchester nursery assistant Anouska, who says she will miss "music, sex, peanut butter and books".
She also picked up the most nominations from her fellow housemates to be evicted, and viewers can vote now on whether or not she gets the boot next Friday.
Anouska was first inside the house - and could be first out
She was followed by 32-year-old fish trader Cameron from the Orkney Islands - who says he will miss "the sea and my dog".
They were followed by followed by 23-year-old waiter Federico from Glasgow, chef Gos, 31, from Southall, west London, and data manager Jon, 29 from Staines, Surrey.
Sales manager Justine, 27, from Leeds was next to enter, and she was joined by 23-year-old Nush, from Malvern, Worcestershire, and IT administrator Ray, 25, an Irishman living in London.
Liverpudlian Scott, a 27-year-old marketing co-ordinator, and 26-year-old Sissy, a fashion designer also from Liverpool followed, while Steph, 27, from Birmingham and Tania, 22, from Kilburn, north-west London were the final pair to enter.
Ray hopes he can relax inside the house
Jon, Scott and Federico join Anouska in this week's vote for eviction.
More than 10,000 hopefuls applied to be on the show, from which producers picked 2,700 to audition.
Footage from the house will be shown in nightly updates on Channel 4, while its pay-TV offshoot E4 will carry live coverage.
Producers say the show is returning to its original format after last summer's split into rich and poor halves of the house was deemed a failure.
But one added twist will be that housemates will have to bet at least 50% of their food budget on their weekly tasks - up from the previous 10%.
Last year, more than nine million viewers turned in to see 22-year-old IT worker Kate Lawler, from south London, win the contest. She is now a presenter on Channel 4's breakfast show Rise.
Big Brother, first shown in Holland in 1999, has become a worldwide hit, broadcast in 22 countries.