We all love a good quiz. So here's a question - when did ordinary contestants turn into the pro-quizzers of today? Giving the answers are Victoria Coren Mitchell, Judith Keppel, Chris Tarrant, Mark Labbett, Nicholas Parsons and many more. Narrated by Ben Miller.

Documentary

Ben Miller, Nicholas Parsons, Mark Labbett, Shaun Wallace, Chris Tarrant, Judith Keppel