Dr Knowles and Professor McCork attempt to ask the almost impossible question 'How many plants are there in the world?' Backstage, McCork unveils his mysterious Megaphone of Truth, an odd contraption which makes it impossible to lie. When it comes to Colin's turn, he has an awful lot to get off his chest.

McCork and Hucklebuck attempt to break the record for the world's biggest ice cream cone in the Brain Freeze studio and Dr Knowles answers the question 'Can ice cubes sink in water?' What can possibly go wrong?

Dr Knowles and Professor McCork ask the question 'Are we all related?' Meanwhile, off air, Colin discovers an old treasure chest owned by his great great great great uncle Percy. Will the Brain Freeze floor manager embrace his swashbuckling family tradition as a salty sea dog?