John Humphrys asks the questions as four famous faces brave the black chair. Mitch Benn answers questions on Peter Cook, BBC News presenter Reeta Chakrabarti on the life and poetry of John Keats, one half of Sam and Mark, Mark Rhodes, on the World Wrestling Federation and double Olympic triathlon gold medallist Alistair Brownlee on the Yorkshire Dales.

John Humphrys asks the questions as another four famous faces brave the black chair. Tonight's contenders and specialist subjects are BBC Watchdog presenter Michelle Ackerley on classic TV series Columbo, The Wine Show expert Joe Fattorini on the line of longitude two degrees west, Instant Gardener Danny Clarke on Sir Garfield Sobers and comedian John Finnemore on the ghost stories of MR James.