“Fiction writers, we tend to make things up,” he says.

“But if you have the president there and you’re writing about a president, that’s wonderful. Because he’ll tell you, ‘This is what the Secret Service would do, here’s what they wouldn’t do… here’s what might happen at the White House, here’s how it wouldn’t happen’. So that’s fun.”

The 31st instalment of 76-year-old Patterson’s series about detective Alex Cross was published recently and Amazon Prime Video is developing a TV series that he hopes will “compete with some of the wonderful detective stuff you already have on the BBC. Happy Valley – that’s one of my favourites”.

A lot of Patterson’s books “are about our darkest fears – things that go bump in the night and night terrors” – and he admits to getting scared by his own writing.

“When I’m writing, if I don’t feel it, my fear is the reader won’t either. So if it’s supposed to be a frightening scene, if I’m not feeling it, if I’m not surprised then I don’t think the reader will be.”

Patterson has plenty to be getting on with. He’s always working on “four or five things at the same time… I never have writer’s block.

“Part of the reason is I can just jump to another project. Stressing over things is not helpful, I think. Sometimes when you let it go and you keep writing, all of a sudden something would pop out of thin air.”

For Patterson, inspiration can come in strange places – such as during a recent visit to the Jersey Shore with wife Susan on a “really windy, cold, rainy day. We all went for a walk over to the ocean and got on the beach.

“I was out there about 10 minutes and I said, ‘Screw this, I’m going back to the hotel’. There was a little road right in front of the hotel and this man was going by on a bicycle…

“I waved to him and a word came into my mind. Just based on that word, I went to the hotel room and wrote five pages for a new novel.”