First Night: Celebrity Big Brother, Channel 4

Who's in the house? That's a good question

Many people have trouble sticking to their New Year diets; but Channel 4's determination to shed weight seems to know no bounds. As Davina McCall (apparently, though I wouldn't have recognised her - what does she think she's doing scraping her hair back like that?) announced at the start, this year's Celebrity Big Brother is the longest yet: 25 days of television without substance or purpose.

Last year - Chinese Year of the Cat - saw Chantelle Houghton, a fake celebrity, emerge triumphant from the Big Brother house, a fully-fledged star. This year a rumour ran round that, in a spasm of post-post-modern irony, Jade Goody, made famous by reality television, was to enter the Big Brother house. This turned out to be untrue; but the casting of this year's series still inspires some thoughts on the nature of modern celebrity. Does Jermaine Jackson, the only male Jackson apart from Michael to have enjoyed solo success, count as a star in his own right, even though few of the other inmates had any idea who he was? Is his celebrity just a facet of his brother's notoriety? (In answer to a question from Davina, Jermaine said that Michael would probably be watching: "He has a way of seeing everything." Suspicions of divinity confirmed, then.)

Given the warmth of the crowd's reception for Jo O'Meara - the one in S Club with the big chin who could actually sing - why did her solo career crash, while her prettier, less talented colleague Rachel Stevens had a string of hits? Clearly, popularity and commercial success are only tangentially related. And why did H from Steps feel the need to "come out" in The Sun prior to the programme, when those of us who have followed his career thought he had come out some years ago?

The biggest star in the house is probably Shilpa Shetty, an ex-Bollywood megastar who, as she confessed in her pre-admission interview, expects to find life hard without an entourage; but her celebrity has no purchase in Britain; none of the other celebrities had the faintest idea who she was. Almost everybody, on the other hand, knew who Leo Sayer was.

Otherwise, we have Ken Russell, optimistically self-described as "the most famous English film-maker", and at 79 having trouble with the stairs; Danielle Lloyd, disgraced former Miss Great Britain and girlfriend of Teddy Sheringham, who is reported to believe that Winston Churchill was America's first black leader; Donny Tourette, lead singer of the band Towers of London, who listed among his pastimes spitting and "never lifting the seat", and whose leering, two-fingering procession into the house lifted him from near-anonymity to panto-villain status; Cleo Rocos, former sidekick to Kenny Everett; and Dirk Benedict, Face from The A-Team.

Finally, and most oddly, we have Carole Malone, a Sunday Mirror columnist, who has disapproved publicly and virulently of Big Brother. She said she could not resist being at the centre of a story "every journalist in the country" wants to write about. Every journalist? Some journalists were looking forward to spending an evening finishing a Joseph Conrad; instead, we get dispatched to the Heart of Darkness. The horror! The horror!

How many have you heard of?

Leo Sayer, 58, Singer from the late 70s who recently reappeared at number one Odds: 4-1

Dirk Benedict, 61, Starred as Templeton 'The Face' Peck in 'The A Team' two decades ago. Odds: 5-1

Ian 'H' Watkins, 30, Believes people see him as 'the blond knob from Steps'. No longer blond. Odds: 5-1

Jo O'Meara, 27, Former member of S Club 7, now turned to dog-breeding. Odds: 6-1

Shilpa Shetty, 31, Bollywood star who hopes every Indian will be proud to see her on 'Big Brother' Odds: 8-1

Donny Tourette, 25, Singer from punk band Towers of London entered the house to chants of 'Who are you?' Odds: 8-1

Danielle Lloyd, 23, Stripped of Miss England title because she dated competition judge Teddy Sheringham. Odds: 10-1

Ken Russell, 79, Film director entered house unsteadily, telling Davina McCall 'I don't want to go.' Odds: 10-1

Carole Malone, 47, 'Sunday Mirror' journalist who wrote that Big Brother contestants are 'a bunch of morons'. Odds 12-1

Cleo Rocos, 44, Writer and actress who played Miss Whiplash in 'The Kenny Everett Show' in the 1980s. Odds: 12-1

Jermaine Jackson, 52, Former member of Jackson 5 and staunch supporter of his brother. Odds: 14-1