NBC has revealed the identities of the 21 contestants competing on The Biggest Loser's tenth season, which will premiere Tuesday, September 21 at 8PM ET/PT and feature a "paying it forward" theme.

The 21 contestants were cast from seven cities --  Atlanta, Boston, Detroit, Los Angeles, Oklahoma City, Phoenix, and Portland -- that The Biggest Loser viewers will see trainers Bob Harper and Jillian Michaels and host Alison Sweeney travel to during the season's premiere.

During their visits, each trainer led community fitness challenges (a one-mile race, a 500 step-up competition, etc.) in which three of the 21 contestants competed and the first two finishers received a spot at The Biggest Loser ranch.  The third-place finishers then returned home and worked out on their own before they later received a second chance to compete at the ranch.

As in previous seasons, the contestant who has the highest weight-loss percentage at the end of the season will win a $250,000 grand prize.

The Biggest Loser's tenth-season contestants are:

- Jesse Atkins, a 28-year-old law clerk from St. Paul, MN

- Montina Cooper, a 35-year-old professional singer and songwriter from Houston, TX

- Jessica Delfs, a 27-year-old professional bridal consultant from Tucson, AZ

- Richard Deroque, a 54-year-old pediatric physical therapist from Conway, AR

- Alfredo Dinten, a 43-year-old futures commodity trader from Staten Island, NY

- Sandy Dolan, 30-year-old stay-at-home mom and student from Ft. Worth, TX

- Brendan Donovan, a 32-year-old special education teacher from Boston, MA

- Tina Elliott, a 58-year-old retired homemaker from Boring, OR

- Sophia Franklin, a 28-year-old high school counselor from Germantown, MD

- Patrick House, a 28-year-old sales representative from Vicksburg, MS

- Adam Hurtado, a 26-year-old non-profit manager from Santa Ana, CA

- Allie Ishcomer, a 22-year-old student from Moore, OK

- Burgandy Keel, a 25-year-old stay-at-home mom from Eagle Mountain, UT

- Shanna Masten, a 38-year-old math teacher from Pima, AZ

- Lisa Mosley, a 31-year-old sales representative from Norman, OK

- Mark Pinhasovich, a 31-year-old bartender and recruiter from East Brunswick, NJ

- Corey Pinkerton, a 27-year-old life coach from Fairbanks, AK

- Elizabeth Ruiz, a 31-year-old medical assistant from Lawrence, MA

- Aaron Thompkins, a 29-year-old graphic designer from Kent, OH

- Ada Wong, a 27-year-old high-tech company project coordinator from San Francisco, CA

- Anna Wright, a 39-year-old administrative assistant and songwriter from Atlanta, GA