This week Ant and Dec are joined live in the studio by Star Guest Announcer Sharon Osbourne.The boys voyage into the unknown once again in Ant v Dec.Lucky viewers are given the chance to win a holiday to Las Vegas courtesy of The Super Computer, and live game Vegas or Bust.Ant and Dec go Undercover for the second time this series.Riverdance perform a special St Patrick's Day performance in the End of the Show Show.And of course, one lucky member of the studio audience will be playing to win the contents of a commercial break on the only show on telly that says ‘Don't just watch the ads – win them!'