William Goldman, author of the hilarious Hollywood exposé Adventures In The Screen Trade, famously said of the movie business: “Nobody knows anything. Not one person in the entire motion picture field knows for a certainty what’s going to work.

Every time out it’s a guess and, if you’re lucky, an educated one.”

And nowhere was this more obvious than on the set of the first Star Wars film, as production supervisor Robert Watts, special guest at this week’s edition of The Space, experienced firsthand.

“The studio didn’t get it,” he says from his Wadhurst home. “They gave us a hard time throughout the shooting.

“[20th Century] Fox were in difficult times. They hadn’t had any hits and saw sci-fi as box office poison.”

Star Wars, the tale set a long time ago in a galaxy far, far away, was a true cinematic phenomenon, and a rite of passage for anyone now under the age of 45.

“When Star Wars hit, Fox’s price on Wall Street doubled overnight,” says Watts, who had previously worked on the James Bond movie You Only Live Twice and Stanley Kubrick’s stunning 2001: A Space Odyssey.

“They got their just desserts though. They didn’t believe in the movie, so they never tied in for a sequel or any of the merchandising rights...”

Having gone to Kabul to work as associate producer on the arthouse movie Meetings With Remarkable Men, Watts missed the initial media storm when Star Wars struck gold.

“Back then I couldn’t make a phone call to England and there was no television,” says Watts. “We had a telex machine in the office and I kept in touch by reading Time and Newsweek.

“It was only when I picked up a copy of Time and saw six to eight pages of Star Wars colour photographs, I knew that it had been a success.”

Watts worked with George Lucas on both sequels – The Empire Strikes Back as associate producer and Return Of The Jedi as co-producer.

And it was while doing pick-up shots at Industrial Light And Magic’s Californian base for The Empire Strikes Back that he was invited onboard another amazing movie franchise.

“George Lucas came through, handed me a script and said, ‘Let me know what you think,’” says Watts. “It was Raiders Of The Lost Ark. I read it and thought it was really exciting.”

Watts alternated between Indiana Jones movies and Star Wars – even making history by taking a role in Return Of The Jedi.

“I appeared very briefly in an ATST walker, alongside the director Richard Marquand, who is no longer with us,” says Watts.

“I’m the one who gets ripped out of the cab and thrown to the ground by Chewbacca.

“The ATST Walker pilot was called Lieutenant Watts. When I did National Service I became a second lieutenant and when I got out, I was told I had been promoted – to Lieutenant.

“I’m the only person in the Star Wars movies playing themselves!”

After Indiana Jones And The Temple Of Doom wrapped in 1984, Watts produced an even more challenging project.

Who Framed Roger Rabbit combined live action and traditional cell animation in a knockabout private detective caper starring Bob Hoskins.

“Jerry the mouse had danced with Gene Kelly [in Anchors Aweigh] but it was on a locked-down camera with flat lighting to make it easier,” says Watts.

“We decided to do it without any of that – with contrasting lighting, camera moves and everything.

“Not many people could achieve what Richard Williams, the head of animation, did before computers. Every cell was hand-painted, rendered and given a solid 3D effect. It was a nightmare – the toughest film I ever did.”

Watts is a great believer in doing things for real over CGI effects.

“One of my favourite shots ever was in Temple Of Doom when the rope bridge falls apart,” he says. “That shot was a one-off. There were four steel cables through the rope bridge which all had to be cut using a radio controlled cutting device. If three had gone and one hadn’t, we would have been in deep s***!

“With CGI, I believe you miss the excitement of shooting that comes off the screen.”

Although 75-year-old Watts hasn’t made a film since Steven Seagal vehicle On Deadly Ground in 1994 (“We were in an Eskimo village in May, just as everything was beginning to melt!”), he has just set up his own production company in Oakland, California, with plans to make a new movie based on a true story.

“It’s about a guy who got a permit to plant industrial hemp in Nicaragua,” says Watts.

“The US told the Nicaraguan government he was growing marijuana. The DEA came and burnt his whole field and threw him in jail. As somebody once said, the only thing you get if you smoke hemp is a sore throat! The film is based on his story.”

He still occasionally attends movie conventions, where he finds his photo as an ATST pilot outsells his “behind the scenes” shot making The Empire Strikes Back in Norway every time.

He is amazed by the fanaticism of devotees.

“There’s a motorcycle chase in Indiana Jones And The Last Crusade that we shot after the rest of the film was made,” he says. “Someone realised we needed a chase.

“The whole sequence was shot in Marin County, California, but Sean [Connery] had no beard – he’d shaved it off. The make-up department got him a beard which was as good as the real thing but some of the fans have spotted it – they go through the films frame by frame!”

  • Robert Watts will be in conversation with Lisa Holloway alongside Emmy Award-winning television producer Gub Neal to mark the 20th anniversary of Cracker, the gritty cop series Neal co-created as controller of drama at Granada. The event takes place at Emporium, London Road, Brighton, on Thursday, November 7, starts 8pm, £10/£8. Visit www.thespace.uk.com