It's a Battle of the Duds this week on Hard Quiz.

Returning are Katharina with her expert subject, penicillin; Matt with the Isle of Wight; Marcus, who's desperate to prove he knows something about dinosaurs; and Kate, who's ready to do backflips once more over Olympic gymnast Simone Biles.

Tom Gleeson is ready to take down four contestants foolish enough to have a second try at getting their hands on the Big Brass Mug.

Tom Gleeson is hanging on to the Big Brass Mug until one Hard Quiz expert can prove they deserve it - but with which topic? Australian parrots, cricket bats, bones, or WikiLeaks?