Humphrys pens massive memoir, but admits he’s no Mastermind

For the past 32 years he’s woken at 3.59am every working day so that he’s ready for action on radio 4’s flagship Today programme.

But now, as he prepares for retirement on September 19, John Humphrys has pulled off an even more staggering feat of stamina — writing his 140,000-word autobiography, A Day Like Today, in just six months.

‘Great writers, like J. D. Salinger, have taken ten years to complete a novel,’ observes Humphrys, 75.

‘Sensible people allow at least two or three years to write a memoir. Ask David Cameron.’

But Humphrys concedes that his explosive output follows a protracted delay. ‘I signed the contract nine years ago and never got down to doing it,’ he tells me.

He twice offered to pay back what he describes as a ‘generous advance’ — though ‘not quite as much’ as was paid to David Cameron, who will donate his £ 800,000 payment to charity.

However, his publisher, William Collins, declined Humphrys’ offer and so, finally, he knuckled down to what he describes as six months of ‘hell’.

‘The only diary I kept was when I was 13,’ Humphrys, who also presents Mastermind,

assures me, before insisting that he has a highly fallible memory. ‘I struggle to recall what I did yesterday.’

He acknowledges that the Hutton Inquiry — into the death of weapons expert David Kelly — will feature. ‘There will be a bit of that,’ he tells me. I trust that there will also be ‘a bit’ about his adventurous romantic history which, to date, has seen him father a son and a daughter by his late wife Edna, from whom he separated in the Eighties, and another son with newsreader Valerie Sanderson in 2000.

He enjoyed successive relationships with journalist Catherine Bennett and his current partner, Sarah ButlerSloss, daughter of supermarket tycoon Lord Sainsbury.

Along the way, he had a reverse vasectomy.

Unforgettable, I presume.