CBS has announced the identities of the 11 teams who will be competing on the 21st edition of The Amazing Race, which will premiere Sunday, September 30 at 8PM ET/PT, and revealed the details behind the season's new $2 million grand prize.

Like prior The Amazing Race editions, the members of the 11 teams competing on the show's 21st installment have a pre-existing relationship with one another. One pair is an engaged couple, one couple is married, four teams are made up of friends or best friends, three teams consist of dating couples, one features twin sisters, and one pair of guys are life partners.

The "Life Partners and Goat Farmers" team of Josh Kilmer-Purcell and Brent Ridge may already be familiar to some The Amazing Race viewers, as they are the stars of The Fabulous Beekman Boys, a reality series which aired on Discovery's Planet Green network in 2010 and 2011 and debut a third season on The Cooking Channel later this year.

In addition, the cast will feature Chippendales dancers, a double amputee professional snowboarder, married monster truckers, a world champion lumberjack, a team of substitute teachers, and a heavy metal rocker.

Hosted once again by Phil Keoghan, The Amazing Race's 21st season will introduce a new previously-announced change in which one team may be able to claim a $2 million prize instead of the series' usual $1 million. However the change has a significant catch -- if the team that wins the first leg of the Race eventually beats their 10 competitors in the final leg of the season to become The Amazing Race champions, that victorious pair will double their money. Should any other team win the Race, their prize will remain only $1 million.

The Amazing Race's 21st season covered 25,000 miles and included visits to three continents and nine counties, according to CBS. One of the Race's most infamous Roadblocks will be revisited in the Netherlands in this edition's "Switchback."

The season will also feature the teams taking on tasks such as rappelling 10 stories in Los Angeles, frying an egg on their heads in Indonesia and working as "rat collectors" in Bangladesh, according to the network.

The 11 teams competing on The Amazing Race's 21st season -- and their CBS-released bio information -- are:

"Twin Sisters" Natalie Anderson and Nadiya Anderson

Natalie is a 26-year-old physical therapy student and Nadiya is a 26-year-old project coordinator at Bridge2Peace. They are both from Edgewater, NJ.

"Goat Farmers and Life Partners" Josh Kilmer-Purcell and Brent Ridge

Josh is a 43-year-old goat farmer, advertising executive and author and Brent is a 38-year-old CEO of Beekman 1802. They are both from Sharon Springs, NY.

"Married Monster Truckers" Rob French and Kelley Carrington-French

Rob is 46-years-old and Kelley is 50-years-old. They are both professional monster truck drivers from Boston, GA.

"Dating Couple" Trey Wier and Alexis "Lexi" Beerman

Trey is a 23-year-old land consultant and former college athlete from Austin, TX. Lexi is a 22-year-old clothing designer from Dripping Springs, TX.

"Friends" James LoMenzo and Mark "Abba" Abbattista

James is a 53-year-old professional musician and former band member of White Lion and Megadeth from Burbank, CA. Mark is a 45-year-old entertainment lawyer from Denver, CO.

"Dating Divorcees" Abbie Ginsberg and Ryan Danz

Abbie is a 31-year-old dance instructor and choreographer from Encinitas, CA. Ryan is a 35-year-old financial service company owner from San Diego, CA.

"Chippendales Dancers and Best Friends" Jaymes Vaughan and James Davis

Jaymes is a 30-year-old Chippendales MC and James is a 27-year-old Chippendales dancer. They are both from Las Vegas, NV.

"Engaged Couple" Rob Scheer and Sheila Castle

Rob is a 52-year-old lumberjack and entrepreneur from Ketchikan, AK. Sheila is a 44-year-old retail manager from Pigeon Forge, TN.

"Best Friends" Caitlin King and Brittany Fletcher

Caitlin is a 24-year-old special education teacher from St. Louis, MO. Brittany is a 25-year-old in medical device sales from Chicago, IL.

"Best Friends and Substitute Teachers" Gary Wojnar and Will Chiola

Gary is a 52-year-old from Livonia, MI and Will is a 53-year-old from Dearborn Heights, MI. They are both substitute teachers.

"Dating On and Off Couple" Amy Purdy and Daniel Gale

Amy is a 32-year-old motivational speaker and snowboarder, who is a double amputee from Las Vegas, NV. Daniel is a 36-year-old executive director from Crested Butte, CO.