Big Brother 2015: Timebomb goes off sooner than expected as first housemate is booted out after just 60 minutes

Simon Gross said he was pleased to have had 'five minutes of fame'

Simon Gross leaves the Big Brother house (PA)

The Big Brother house threw open its doors to another crop of housemates - and immediately evicted one in a shock twist.

A wannabe prime minister, a polyamorous model and a self-proclaimed "chav" were among the contestants who will compete to be crowned winner.

But in a shake-up to the usual format, one unlucky contestant was shown the door just an hour after he walked up the steps into the famous house.

Simon Gross, also known as "Mr Showbiz", was booted out after he pulled a pin on a Big Brother "timebomb" which sealed his fate and ordered his eviction.

But the 46-year-old from Kent, who has been in showbusiness for more than 30 years and kept bursting into jazz hands, was philosophical about his early eviction.

Smiling he told host Emma Willis: "It's fine - it's all showbiz. I got my five minutes of fame. For my five minutes of fame it was fantastic. Those guys are fantastic and I would have loved to have been with them."

He added: "Darling, I've had so many rejections this is just one of many. It's all showbiz. I would have been fabulous but that's how it goes. It's showbiz.

"I think the people I've met are really young, fun, attractive, interesting - I think it's going to be a fantastic summer.

"You haven't seen the last of me yet."

His departure still leaves 15 people in the Big Brother house, in the show's 15th year.

The famous house has undergone a retro James Bond-style makeover for this series, with a diamond-studded bedroom, new, bigger, pool - and a fish tank in the bathroom.

And an assortment of personalities from all walks of life will be competing to win over the public and be named Big Brother champion.

They include Chloe Wilburn, 25, from Doncaster, a self proclaimed "chav" whose dream is to move to Benidorm and Kieran Mcleod, 30, from Birmingham, former basketball player who went into food business.

They are joined by Jade-Martina Lynch, 24, from a polyamorous model from Dublin, wannabe prime minister Joel Williams who at 19 is the youngest councillor in Wales, and Cristian MJC, aka Matthew Clarkson, 20, a rapper and biomedical science student from London.

Also competing are Harriet Jackson, 22, a cafe worker from London, identical twins Amy and Sally Broadbent, 27, from Manchester, and breast-obsessed law student Adjoa Mensah, 22, from Manchester.

They are joined by Nick Henderson, 19, from Hertford, who has been expelled from two schools, demolition man Danny Wisker, 29, from Margate and argumentative law student Sarah Greenwood, 24, from Manchester.

Aaron Frew, 24, a model from Nottingham and former X Factor contestant Eileen Daly, 51, from London, will also be competing.

Jack McDermott, 23, known as pie-face, from Plymouth, is already hot favourite to win according to bookmaker Coral which gave him odds of 3-1.