Alexa and Carlos PenaVega, Chaka Khan to join 'Dancing with the Stars' season 21 cast

Dancing with the Stars fans, the season 21 cast is shaping up! Married celebrity couple Alexa and Carlos PenaVega are officially signed up, as well as long-time R&B artist Chaka Khan.

The new recruits will join Bindi Irwin, Victor Espinoza, Nick Carter and Grier Hayes in the competition.

The VegaPenas couldn't be more excited to be vying against each other on the dance floor. Embracing their status as the married couple, the two posted a cute "proposal" video to make the announcement.

The cast so far includes a social media star, veteran performers, athletes and more, ranging in age from 15 to 62.

Alexa is best known for her role as Carmen in the Spy Kids franchise. Her husband is a member of the band Big Time Rush, which had a Nickelodeon series of the same name. Khan is a Grammy-winning recording artist with a career spanning four decades, including hits like "I'm Every Woman."

Irwin, the daughter of "Crocodile Hunter" Steve Irwin, was the first to officially join the cast.

Victor Espinoza, the jockey who won the Triple Crown in 2015 while riding on the horse American Pharoah, will also be dancing. Prior to Espinoza's win, the last time the Triple Crown feat had been accomplished was in 1978.

Entertainer Nick Carter, 35, is best known for being a member of the Backstreet Boys.

ABC has also announced many of the professional dancers that will join the show this season, and fans will recognize some familiar faces.

PHOTOS: Dancing with the Stars season 21 professional dancers

The celebrity cast announcements will continue before the show's fall premiere.

Dancing with the Stars season 21 will premiere Sept. 14 on ABC at 8 p.m. ET | 7 p.m. CT.