In "The Twilight Saga: Breaking Dawn - Part 2," the franchise's final installment, fans can expect "epic confrontation," Maggie Grace told MTV News. But it turns out the cast still found time to let loose and bust a move on set.

Grace and co-stars Mía Maestro and Casey LaBow spilled all the details about their choreographed dance-off during our San Diego Comic-Con live stream on Thursday before heading to the "Twilight Saga: Breaking Dawn - Part 2" panel in Hall H. According to LaBow, there are "surprises" in store for viewers of this final "Twilight" film, but their on-set dance performance was a way to surprise and celebrate the film's director, Bill Condon.

"It was meant to be a thing for Bill," LaBow said. "Everybody on set knew about it except for Bill."

"We wanted just to surprise him and we just wanted to move and dance and have fun," Maestro added.

In addition to celebrating Condon, the dance-off had another goal for those involved. After six weeks of filming in the same area, Grace said they needed to mix things up.

"We needed the morale boost, I think, to unite us all in vampirehood and joy," she explained.

The dance was performed to the '80s jam "Sweet Dreams" by Eurythmics, Maestro revealed. While she said she was the organizer of the dance-off, she also gave credit to everyone who participated in making it happen.

"It was a huge group effort," Maestro said.

While live-stream viewers may not have gotten to see them perform the full dance, Grace did reveal one part that was fitting, given that all three actors portray the vampires of the Denali coven in "Breaking Dawn."

"There's a vampire thing in there," Grace said. "A little 'Thriller.' "

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