Stars from the worlds of singing, acting, modeling and sports are coming together to battle it out on the dance floor on the new season of "Dancing with the Stars."

The season nine cast includes singers Mya, Macy Gray and Aaron Carter; actors Ashley Hamilton, Melissa Joan Hart and Debi Mazar; models Joanna Krupa and Kathy Ireland; reality stars Mark Dacascos and Kelly Osbourne; entertainer Donny Osmond; athletes Chuck Liddell, Louie Vito, Natalie Coughlin and Michael Irvin, as well as former Republican Majority leader Tom DeLay.

Who will rule the dance floor, and who will fall short under pressure? Find out when "Dancing with the Stars" premieres September 21.