More acts show off their stuff in the third round of auditions, hosted by Ant and Dec. With fingers firmly on the buzzers, and arse cheeks firmly clenched, judges Simon Cowell, David Walliams, Amanda Holden and Alesha Dixon sit through a line-up of wannabe singers, dancers and variety acts all hoping to win the prize of £500,000 and a slot at this year's Royal Variety Performance.