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 said.
"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 entered 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 said.
"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 at 66-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 said.
"It's going to be mad, it's going to be fun, it's going to be terrifying. Bring it on!"
After being photographed entering the house late last year it was no surprise to see TV presenter, DJ and podcaster, Flex Mami (real name Lillian Ahenkan) appear in the show.
"Big Brother intrigues me," she said, "my life is one big social game."
This 21-year-old blonde bombshell is a student from Sydney and is hoping her rivals underestimate her - before she reigns supreme.
“I’m going to act dumb and play smart,” Tilly insisted.
“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.
This 25-year-old basketball player from Melbourne has had a rough ride.
After losing his mum to cancer, Marley is motivated to win so he can take care of his dad.
"Mum gave me one thing to do and that was to look after dad." Marley said.
"I can hear her voice in my head telling me to go for it and win this whole thing. I'll do anything to get to the end."
Laid-back Nick is a 29-year-old colour-blind house painter from Adelaide.
While in the house, Nick had a "bromance" with fellow contestant Daniel.
Ari is a 22-year-old student from Sydney's Eastern Suburbs.
He's highly intelligent and ambitious with plans to be Australia's youngest Prime Minister.
The law, communications and neuropsychology student believes he can charm his way into some fake friendships in the house to take out the Big Brother title.
Carlos is a 39-year-old teacher from Colombia who fell in love with Australia while holidaying here; now he lives in Western Australia.
He's loud and proud, and an avid coffee lover.
His friends call him "loco" and he wanted to spread some positivity around the Big Brother house.
AFLW recruit Jess, 28, from Victoria is a former North Melbourne defender/midfielder turned PE teacher.
Jess thinks her patience and bubbly nature should make it easy to make friends in the house, but worries her competitiveness may lead to some enemies.
Sid is a 34-year-old creative genius from Western Australia.
The Indian-Australian artist was born in London, raised in Kenya and spent his teenage years in Australia where he now works as a high-school art teacher.
Sid plans on playing the smart game in order to win the prize money for his future wedding.
Self-proclaimed "Princess Char" is a 24-year-old sassy and single stylist from Queensland who thrives in Cheetah print.
She's ready to go whatever it takes to get to the finals and, if she wins, claims she'll put the prize money towards "something obnoxious" before popping the rest in her savings.
Renata, 45, is a cool and no-nonsense mum from Lithuania who isn't afraid to speak her mind.
Studying nursing as she works as a flight attendant in Adelaide, Renata wanted the prize money to help provide for her kids and to travel back to Lithuania.
Another flight attendant!
Christina, 22, from Victoria is energetic, fun loving and a hopeless romantic who is ready to establish as many emotional connections as possible.
This magician cross stand-up comedian certainly has a few tricks up his sleeve.
Christopher from Queensland admits he can be polarising but is confident in his powers of manipulation.
The 37-year-old was hoping to meet the woman of his dreams in the Big Brother house.
Marketing consultant from Perth Michael may look adorakable, but he is also calculated and cunning and was ready to do whatever it took to win the game.
The 29-year-old loves mischief, dislikes alpha males and is always ready for an adventure.
Chatterbox Mitchell is a 26-year-old 2D animator from Queensland who loves everything about nature, particularly bird watching.
His game plan was to observe each housemate closely to figure out when to strike.
He's also an open book and not afraid to show his vulnerable side.
Gold Coast Ironman Max, 29, is an elite athlete who also works in events and marketing.
Max is always ready to forge new friendships but is also highly competitive.
Notice a resemblance?
Mary from Victoria is the mother to Married At First Sight star Martha Kalifatidis. And now, it's Mary's turn to try the reality TV game.
The stay-at-home mum of two, 56, is ready to step out of her comfort zone and have some fun.
She's also hoping to win over her fellow housemates with her cooking, confessing: "I want to get all those b*stards fat".
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 ..."
Mitch, 26, is a FIFO worker from WA and he is a force to be reckoned with. The friendly giant reckons he'll dominate each challenge while also bring some childish fun to the house!
Double trouble! One half of the intruder twins Charlotte is looking forward to making some memories with her sister Alex. The 26-year-old is currently pursuing a career in nursing and is keeping her Big Brother strategies close to her chest.
Look familiar? Charlotte's twin Alex, 26, is a fun fashionista with a strategic side. The Victorian is a registered nurse and recently moved into her own home with her partner. We expect the Big Brother house will prove to be a very different living situation.
Gabe's plan in the house is to talk sweet and play dirty. This 27-year-old Queensland trampoline park attendant is a passionate foodie and just as passionate about winning.
Mother-of-three Adriana, 53, is fun, playful, and a little bit naughty. She's planning on giving the younger contestants a run for their money while also having a blast in the Big Brother house.