Christopher Biggins, former glamour model Sam Fox and Loose Women's Saira Khan are among the famous faces who have entered the Celebrity Big Brother house.
Pantomime star Biggins, 67, was the first to enter the house and issued a warning to bullies.
He said: "I don't like bullies and I will not sit back and see someone bully someone else. I would not put up with that. Bullies beware."
The latest series of the Channel 5 reality TV has seen a total of 15 well-known personalities, both British and American, go into the house.
The first American celebrity to enter the house was 33-year-old Frankie Grande.
The musical theatre star is the older half-brother of pop superstar Ariana Grande and recently starred on the American version of Big Brother.
EastEnders star Ricky Norwood, best known as Fatboy, also entered the house.
Channel 5 did not censor the video message as it introduced the fifth housemate, Renee Graziano.
Graziano, 48, is best known to American audiences for her role in reality show Mob Wives, which follows New Jersey women who are connected to the mob either through family or marriage.
Geordie Shore's Marnie Simpson said in her introductory message that she was bisexual and would be "after girls as well as boys" in the house.
Radio and TV broadcaster James Whale said he and former Ukip leader Nigel Farage are "quite pally".
The 65 year old was a host on LBC from 2008 until 2013 and currently hosts a show on BBC Kent.
Former Danity Kane singer Aubrey O'Day, 32, did not mince her words as she was introduced.
She was the breakout star of reality show Making The Band 3 but was fired from the group in 2008 after a row with mentor P Diddy. She reunited with them in 2013 and is now a member of duo Dumblonde.
Reality TV star Stephen Bear from Ex On The Beach swore repeatedly while being interviewed by host Emma Willis.
The 25 year old is the former flame of Geordie Shore and Loose Women regular Vicky Pattison.
Former X Factor contestant Katie Waissel described herself as being "not away with the fairies, I'm very grounded".
She starred in the 2010 series of the singing competition.
Waissel referenced her controversial stint on the ITV singing show, saying: "I just don't want to even address it. When I was on the X Factor I think people got to see the wrong side of me.
"Life on the X Factor was definitely an experience ... I wanted to shut myself in a dark room and I pretty much did that for a long time."
Other names who entered the house include former The Only Way Is Essex, Lewis Bloor and Grant Bovey, the ex-husband of Anthea Turner.
Bovey was declared bankrupt in 2010 before Turner divorced him after he had an affair.
He gave a frank introductory message saying he had made "mistakes in my life".
He said: "If I could have my time again, there are certain things I would change. Public perception (of me) is not great at all. Once people decide they want to portray you like a villain it's very difficult to break those shackles.
"I have lots of regrets. I regret all the hurt I caused ... to my first wife and to Anthea, there are things there I am not proud of."
Playboy model Chloe Khan, 25, described herself as being a self-proclaimed princess and "quite bloody confident".
She appeared on the X Factor in 2010 under the name Chloe Mafia.
One of the last people to enter the house was Heavy D, real name Colin, from the UK series of Storage Hunters.
Biggins was made the "secret boss" of the Celebrity Big Brother house as contestants were given their first task.
Contestants were informed a house boss would be chosen while they enjoyed a silent disco.
After a public vote, Biggins was told he had won the title, which gave him "special powers" including immunity from the first eviction and control over the nominations.
The rest of the contestants were told Biggins had been chosen and it was also revealed to them that the task was a joke.