The remaining three celebrities locked inside the Big Brother house are to find out on Friday which of them the public has chosen to win the charity TV special.

TV presenter Les Dennis, glamour model Melinda Messenger and singer Mark Owen have survived 10 days of living under the glare of cameras as part of the Channel 4 show.

Comedian Sue Perkins, 33, was the latest housemate to be evicted after the public overwhelmingly voted for ex-Take That star Owen to stay.

A winner will be chosen by viewers when the series ends on Friday night.

Les Dennis: Talking to chickens

The show started well in the ratings with the first show in which the celebrities were unveiled attracting 7.2 million viewers.

But there has been a dramatic decline in the show's popularity with an average of 4.2 million tuning in nightly.

After leaving the house on Thursday, Perkins spoke of the tension that had been growing between her and other contestants.

Speaking about Messenger, she said: "I could not have an emotional conversation with her. I was upset at one point and it was like talking to a brick wall.

Psychiatrist

"Every time I tried to say something about what I felt she looked at me as though I was a freak."

Melinda: Has suffered from Vulcan and Darth Vader comparisons

Perkins said she had urged Dennis to see a psychiatrist after he poured his heart out about his marriage to actress Amanda Holden.

"The thing about Les was that he was the only person to say he wanted to win," she said.

"When someone says they want to win you are very aware of the cameras and relationships with people," she said.

"Les kind of tortured himself and beat himself up."

But she backed Owen to win the contest, calling him the "most rounded personality" and "the most fun".

There have been increasing concerns over Dennis' mental state after he was filmed sitting in the garden looking dejected and talking to the house chickens and to himself.

Animated

Mark: Has new fans in evicted contestants Anne Diamond and Sue Perkins

The 48-year-old has also been having frank and open conversations with fellow housemates about his marriage and his son Philip, who he says he does not see enough.

But his agent insisted Dennis was holding up well under the pressures of being watched 24-hours a day.

"Les is naturally very caring and a genuinely lovely man. He is very animated and saying what he thinks which makes it all the more watchable," said Pat Lake-Smith.

Former daytime TV host Anne Diamond and musician Goldie were evicted by viewers earlier this week.

None of the contestants are being paid for taking part, and the show will raise money for the Centrepoint homeless charity, the National Missing Persons Helpline, the Rethink mental illness charity and the Samaritans.