MacManus and Murgatroyd were both members of the "Dancing with the Stars Troupe," the new six-member dance performance group the show introduced during last spring's twelfth season, while Val Chmerkovskiy is the younger brother of veteran professional partner Maksim Chmerkovskiy.
The 12 celebrity participants -- which ABC announced Monday -- competing on Dancing with the Stars' thirteenth season are actor David Arquette, NBA basketball player Ron Artest, transgender advocate Chaz Bono, model and George Clooney ex-girlfriend Elisabetta Canalis, former The Hills star Kristin Cavallari, legal commentator Nancy Grace, Keeping Up with the Kardashians sibling Rob Kardashian, fashion expert and former Queer Eye star Carson Kressley, former talk show host Ricki Lake, Iraqi war veteran and All My Children soap star J.R. Martinez, singer and actress Chynna Phillips, and American women's soccer star Hope Solo.
Ballas will be partnered with Cavallari. He previously won Dancing with the Stars' sixth season with Kristi Yamaguchi, eighth edition with Shawn Johnson, and is returning for his ninth season.
Dovolani, who is back for his twelfth season, will dance with Phillips.
Hough -- who missed last spring's edition to film Cobu 3-D, an upcoming danced-themed movie that will represent his feature film debut -- will be partnered with Lake and participating in his eighth Dancing with the Stars edition. He previously won Dancing with the Stars' seventh season with Brooke Burke, tenth season with Nicole Scherzinger, and eleventh season with Jennifer Grey.
Johnson will be competing with Arquette and participating in her tenth season. She won Dancing with the Stars' ninth season with Donny Osmond and last spring's twelfth edition with Hines Ward.
Schwimmer, a former So You Think You Can Dance contestant, will be participating in her fifth Dancing with the Stars season and compete with Bono.
Smirnoff, who is back for her tenth season, will be partnered with Martinez.
Trebunskaya, who is participating in her eighth season, will dance with Kressley.
MacManus will be paired with Grace, while Murgatroyd will dance with Artest and Val Chmerkovskiy will be partnered with Canalis.
Dancing with the Stars' thirteenth season will premiere Monday, September 19 at 8PM ET/PT with a two-hour broadcast.
All 12 celebrities will perform a Viennese waltz or cha cha routine with their professional partner during the premiere, and the couple with the lowest combination of the judges' scores and home viewer votes will be eliminated on the following night's results show.
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