This 48-year-old real estate agent is described as a "loose cannon" who is putting everything on the line to win.
"I'm going to be the greatest player of Big Brother in the world," Daniel says.
"The bar's going to be raised this year. I don't quit. I walk my talk. I will win Big Brother."
Leaving her three young children at home for the first time, she's entering Big Brother's house with her eyes firmly on the prize.
"Winning Big Brother will save our family farm and my kids will be ok," Melissa says.
"That's all I want for them, to secure their future. Nothing will break me."
The first officially confirmed housemate for 2021, Sarah Jane is also the oldest contestant to enter the show at 65-years-old.
The antique jewellery dealer is a fierce fashion icon and well known to many in the industry.
"I might be the oldest but I have an opportunity to prove to people that you can all put yourself outside of a comfort zone and fly," she says.
"It's going to be mad, it's going to be fun, it's going to be terrifying. Bring it on!"
This 31-year-old account manager from Sydney describes himself as a go-getter, who doesn't do anything half-heartedly.
“I don’t go into anything to lose," Brenton says. "I’m going to use every skill I’ve got, whether its charming them with cooking or charming them physically. There’s not a single challenge that’s going to break me."
But despite his ambition to win, the self-confessed charmer admits he would forfeit his chances if the right person came along, saying: "I'm here to win, but if the right opportunity comes along ..."
After being photographed entering the house late last year it's no surprise to see TV presenter, DJ and podcaster, Flex Mami appear in the first teaser for the show.
The multi-talented social media star, whose real name is Lillian Ahenkan, can be seen strutting down the street.
"Big Brother intrigues me," she says in the clip, "my life is one big social game."
This 21-year-old blonde bombshell is a student from Sydney is hoping her rivals underestimate her - before she reigns supreme.
“I’m going to act dumb and play smart,” Tilly insists.
“My whole life people look at my like I’m a bit stupid. I just want to prove my strength.”
Think Katie Williams, 27, looks like a familiar face? There's a good reason why - she has previously appeared on Australian Ninja Warrior.
The personal trainer and podcast host also has another connection to reality TV. She once dated Married At First Sight groom Mikey Pembroke before he appeared on the dating show.