Battle of the Duds! - Mammalian Sperm, Ada Lovelace, Steely Dan, John Deere Tractors

It's a Battle of the Duds! Tom Gleeson invites four failed former contestants to humiliate themselves again. Vying for the Big Brass Dud Mug are experts in mammalian sperm, Ada Lovelace, Steely Dan and John Deere Tractors.