Cameron and Taylor Henderson, the father and son pair from Ceres, Geelong, fired up the stage during the grand final of Seven's Australia's Got Talent.

The duo, who said they each wanted the other to win the $250,000 prize, captured the hearts of the audience and judges with their ballads.

Judge Brian McFadden thought Taylor was a "superstar", while Dannii Minogue said he was in the zone.

"I can't get my head around how a 17-year-old can perform and sit there and sing with that kind of passion," McFadden said.

"Look, whether you win this show or not, you will be signed after this show ... there will be record companies queuing up to sign you."

Cameron also left the judges tongue-tied with the amazing performance, with Kyle Sandilands calling him brilliant.

"It was heavenly," Sandilands said.

Lara rollerskating sensations Rolling Entertainment started opened the show with a futuristic routine that also mesmerised the judges.

Host Grant Denyer described it as "Avatar meets Mad Max" and said it was amazing.

Voting lines close on Friday noon.