Contrary to performances in The Trip and lots of press reports, which pitch the pair as benign stags, Rob Brydon and Steve Coogan do like each other.

The Trip’s producer Andrew Eaton believes filming the series brought the duo together.

“I think they like each other more now than they did a few years ago. Doing The Trip To Italy made them better friends. I think they would both admit to that.”

Eaton is director Michael Winterbottom’s right-hand man. He has made more than 20 films with Winterbottom, including Tristram Shandy: A Cock And Bull Story, 24 Hour Party People and 9 Songs. He says the challenge of making the Italian follow-up to The Trip’s first series was persuading the comic actors to do another one. “It usually takes about two years to do it. After the first one they said they’d never do it again.

“After the second one everybody had so much fun they said I think we will do another one.”

He believes the key to success will be to wait for a passage of time for enough things to have happened to them before attempting another one.

In the first series, Coogan accepts a commission from The Observer to do a culinary tour of northern England to impress his girlfriend. Miserable with his life, he has a series of one-night stands. In Italy, Coogan and Brydon’s roles are reversed. The latter is distracted from family life.

Eaton says the team wanted to change the dynamic. But the interaction between the two actors remained natural - and hilarious. Coogan even won a Bafta in 2011 for his performance.

The Trip To Italy sees Coogan lead Brydon on a tour in search of the romantic poets, Percy Bysshe Shelley, Lord Byron, John Keats. It is bittersweet, expertly scored, with themes of aging, love, friendship.

Which in part explains its appeal “for men of a certain age The Trip really was true because lots of people go through those kind of experiences.”

The laughs come from Coogan and Brydon’s impressions – favourites being Bond actors and Michael Caine – and their catty, knife-in-the-front exchanges.

It’s all off the hoof, too, confirms Eaton, who lives near Chichester.

“There is an agreed storyline through the series. But the script comes mostly from different conversations that Michael, Steve and Rob have the night before we shoot.

“In the case of The Trip To Italy, [spoiler alert] we knew that Rob was going to have an affair on the journey.

“But what tends to happen is Michael will shoot the meal then stop and do it all again the next day. We keep the bits that work well and add to it.”

Roger Gibson, Chichester International Film Festival artistic director, is a huge Winterbottom and Eaton fan.

“I love the variety and range of their output, from comedy to political drama and documentaries.” Gibson has picked seven collaborations to be shown in a major retrospective for this year’s programme.

Among the selection are the duo’s most acclaimed films: Berlin film festival Golden Bear-winner In This World and Silver Bear-winner The Road To Guantanamo.

Both were filmed in the tribal areas of Pakistan and Afghanistan.

The Road To Guantanamo traces The Tipton’s Three’s accidental journey to the heart of the war on terror. In This World follows two Afghans hoping to find asylum in London.

“Filming in Afghanistan was pretty scary,” reveals Eaton.

“The first time we did it we didn’t realise how naive we were being until after the event. We did two films back to back in Pakistan and I swore never to go back.

“Then we got asked to do A Mighty Heart with Angelie Jolie and we did go back.”

Gibson, who met Eaton at a screening of Ron Howard’s Rush at Goodwood, has picked A Mighty Heart for the selection.

Eaton produced Rush, the engrossing story of James Hunt and Nicky Lauda’s rivalry in the 1976 Formula One season, and he will be joined by its star Daniel Brühl for a Q and A following screenings of Rush and Lauda: 33 Days, Born To Be Wild.

“Winterbottom and Eaton broke new ground with The Trip and Doll and Em,” says Gibson.

“That may have developed from Tristram Shandy where Rob and Steve partly played themselves. “I think it gave them the idea to develop that partnership.”

Eaton is equally proud of another big partnership he has helped develop.

Aaron Sorkin from HBO loved Emily Mortimer and Dolly Wells’ six-part series Doll & Em and the network aired the first season (as did Sky in the UK).

Eaton reveals they are just about to shoot the second series with insecure Hollywood actress Em and her best friend and personal assistant Doll having moved to New York.

“The whole idea partly inspired by The Trip,” explains Eaton.

“In real life Dolly and Em are older friends than Steve and Rob and probably spend more time together with their respective families. So it is less manufactured.

“There are both playing off the same idea, two friends who know each other very well, with a lot of improvisation, but Doll and Em work from tighter scripts.”

The programmes follow series such as The Office, Seinfeld, even Alan Partridge.

“There is nothing particularly original about it. It’s hard to explain why it works. In a sense the fact they look so simple is a testament to the quality of the directors. It’s not that simple to do. It’s takes a lot of skill to make it seem so natural.”