Angela Weiss/ Alberto Rodriguez/
It only takes two to tango, so the dance floor might get a bit crowded when former "American Idol" contestant Pia Toscano performs. Will Mark Ballas' ballroom partner Chelsea Kane get jealous of Mark's real-life partner?
"Dancing With the Stars" co-host Brooke Burke announced that Mark will dance as Pia sings on next Tuesday's results show.
Fellow contestant Chris Jericho admitted to helping initiate contact between Pia and Mark since "American Idol" tapes just across the hall from "Dancing With the Stars." Sparks reportedly flew when the two shared a meal. On the talk show circuit, Mark said they bonded over music because he is a musician in addition to dancer.
New Kids on the Block and Backstreet Boys will also be special guests. "Dancing With the Stars" airs Monday and Tuesday nights on ABC.