Actor, stand-up comedian, panel show host, singer, impressionist - with a CV like that, why would Rob Brydon want to add "chat show host"? Plenty of good prospects have fallen at the chat hurdle on BBC2, from Jeremy Clarkson to Danny Baker, but Brydon perhaps has one advantage. In 2004 he hosted a spoof chat show as his alter ego, the slightly hopeless Keith Barret, discussing relationships with celebrity couples. Tonight we'll find out if he can carry off the trick without having his tongue in his cheek. His guests include an old friend, David Walliams, and a hero - Tom Jones.

Any ad-libbed, improvised show requires a special skill from the players, and in a professional sense they are living dangerously. There was an occasion in Just a Minute when the subject was snapshots. Kenneth Williams was unhappy about one of my decisions, which went against him on this subject, and he began to harass me. Peter Jones and Derek Nimmo joined in, which added to the pressure. In an effort to bring them to order, I said: "I'm sorry Kenneth, you were deviating from snapshots, you were well away from snapshots. It is with Peter, snopshots, er snipshots, er snopshits . . . snop . . . snaps." The audience roared with laughter. I added: "I'm not going to repeat the subject. I think you know it . . . and I think I may have finished my career in radio."

QI, however much it tries to be subtly different, is part of a glorious tradition. When radio first presented panel shows they cast them from those with a proven intellectual background. This mold was broken in the early 1960s, when Jimmy Edwards devised a programme for the Home Service, with himself as chairman, called Does the Team Think?. The panellists were all well-known comedians, Tommy Trinder, Cyril Fletcher and others, who proved that comics were just as intelligent as academics, and usually much funnier.

QI is a direct descendant. And when you have Stephen Fry, and contestants such as Alan Davies, Hugh Laurie and Danny Baker, and a producer of the calibre of John Lloyd, the BBC must be on to a winner.

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