The beginning of principal photography on Star Wars hardly merited a mention around Hollywood. Only the official announcement of Lucas's main casting coup aroused interest at the time. On the morning of 24 March, Variety ran a brief report:

Since their Los Angeles lunch, Guinness and Lucas had talked a lot. Guinness, disinterested in playing a crackpot but quietly impressed by the young director, had suggested making Obi-Wan Kenobi a less eccentric, nobler character. Lucas liked the idea, he thought it would deepen the divide between the goodness of Obi-Wan and the darkness of Vader. Guinness did not come cheaply. While Hamill, Ford and Fisher had accepted $1,000 dollar a week salaries, Guinness's five-figure cheque was supplemented by a two and a quarter per cent share in the film's profits. It would turn out - by several light years - to be the biggest payday of his long and distinguished career.

Kurtz and Lucas had allocated eleven days for the north African part of the shoot. If time pressures were not tight enough, Kurtz had booked a giant Lockheed Hercules C130 cargo plane to transport the mass of props, cameras and lighting equipment home to Elstree. Under the terms of their contract with the charter company, the production was due to be charged $10,000 for every hour the plane was kept waiting on the tarmac.

Lucas, Kurtz and Robert Watts had chosen Tunisia as the location for the desert planet Tatooine, Luke Skywalker's home and the setting for the opening act of the story, because of its strikingly primitive architecture and the co-operative attitude of its government. Officials, happy that the script did not contain anything to offend its predominantly Moslem population, had given clearance to film in previously unseen areas of the country.

As well as the Chott el-Djerid, setting for the exterior of the farm on which Luke lived with his aunt and uncle Bern and Owen Lars, Robert Watts and his location managers had chosen four other main sites in Tunisia. A white-domed settlement on the island of Jerba, thought to be the legendary 'Land of the Lotus Eaters' described in Homer's Odyssey, had been chosen as the exterior of the Mos Eisley spaceport where Luke and Obi-Wan would hire Han Solo and his Millennium Falcon. In the town of Matmata, strange, subterranean, cave-like dwellings carved by the native Berbers to protect them from the sandstorms had been picked to portray the Lars family's underground quarters. A remote canyon, beyond the Chott el-Djerid, served as the scene for Luke' s meeting with Obi-Wan while another, sand dune region outside the city of Tozeur, had been lined up for filming of R2-D2 and C-3PO's arrival on the planet.

The rains that hit the Chott el-Djerid immediately lost the crew a day and the use of two trucks, stranded temporarily in the mud and salt. Working days were soon extended to make every use of available sunlight

Lucas's greatest problems came when he attempted to make use of the technology flown into north Africa, A sizeable chunk of the 510 million budget had been devoted to bringing Ralph McQuarrie's art to life. The respected British production designer, John Barry had enlisted some of Britain's brightest talents to construct the battered hardware of Tatooine, from a vast, 90 ft 'sandcrawler', in which the midget Jawas carried R2-D2 and C-3P0 across the desert, an assortment of robots and Luke's 'landspeeder', a sleek, hovercraft cum sports car.

Yet the sandcrawler was destroyed before it had been before the cameras, flattened one night by the savage Saharan winds. Kurtz asked the crew if they would take Saturday off, except for the production crew, and work on Sunday instead, which they all did. If that was not bad enough, Luke's landspeeder failed to work properly. The vehicle also proved difficult to film without its supports and wheels visible.

Lucas's greatest problems were reserved for his cherished robots, however. Kenny Baker found R2-D2 almost impossible to operate- Baker had to squeeze inside the canister, from where he had to operate switches activating the droid's lights and power, While that was manageable, achieving any fluent movement was beyond him.

'It was very hard to move because it weighed about 70 lbs,' he remembered. Baker, a skilled roller-skater, had suggested putting the robot on rollers. The modification hardly helped. 'Every time I put the left foot forward the right foot went back, when I put the right foot forward the left foot went back. Then they thought they'd put ratchets on the rollers so that it only rolled forwards. That only worked to a certain extent because it was so slow, I could not move each leg more than about five inches at a time,' he recalled.

It was only as he lost patience with the contraption that Baker stumbled on a solution, 'In the end, I rocked it out of anger and frustration one day and it wobbled from side to side,' he said. 'While one leg was in the air I discovered I could move it if I just rocked it from foot to foot. That was the only way I could do it.'

Lucas eventually gave up on using the actor in the desert and had crewmen pull the empty robot across the sand on an invisible wire. The process was almost as difficult. R2-D2 regularly fell over as the cameras rolled.

Baker's frustrations were nothing compared to the torture Anthony Daniels was enduring playing the 'tin man' in the searing desert heat. Daniels's suffering had begun back in London. Costume designers had stripped him naked, covered his body in Vaseline and his private parts in plastic film before casting him head to toe in plaster. Later he had been fitted in a latex suit which left him itching his way through an entire performance of Rosencrantz and Guildenstern. Eventually the burnished gold costume had been constructed out of fibre-glass sections. (There had been fears a plastic version would melt in the desert heat.) The befuddling process of fitting the pieces together was, Daniels complained, 'like fiddling with a Rubik cube.' Most days it took a minimum of two hours. The finished effect was undeniably stunning. The Tunisian crew let out an audible gasp at their first sight of Ralph McQuarrie's original drawings brought to life.

'When I walked out of the tent it was like being a God,' said Daniels. 'Everybody simply froze. In the glare of the desert sunshine was this wonderful golden man.'

Any sense of pride he may have felt proved short-lived. The suit was heavy, the fibre-glass strands irritated his skin, the plates pinched and stabbed him, movement was restricted to jerky footsteps and arm twitches, and it was impossible to drink or relieve himself without the aid of a crew member. Even with two local helpers assigned to protect him from the sun with a parasol, Daniels sweated profusely. He lost, on average, four pounds a day in weight.

At the end of his first day inside the robot's skin the sensitive actor almost quit. 'That first day in the desert, I wore it from seven in the morning until seven at night. I was hysterical by then.' Daniels described the overall experience as 'like living in a biscuit tin with no human contact - a kind of deprivation torture.'

Predictably cast and crew fell victim to the traditional enemy of the Saharan intruder, dysentery. Anthony Waye, an experienced British assistant director, kept a diary of the first days of the Star Wars shoot. 'Cannot abide the filthy hotel, I was one of his earliest entries- Collectively the cast and crew blamed the epidemic on the breakfast boiled eggs. 'Dysentery became boiled egg syndrome. At breakfast everybody ordered boiled eggs, one of the safest things to eat in a place where dysentery is par for the course. The cook had a giant cauldron of eggs and had no system for timing them. You either got one that was rock solid or totally raw - never anything in between,' Waye recalled.

Bunny Alsup was stricken on the first day. The most serious casualty, however, was Stuart Freeborn. In Tunisia to supervise his designs for the desert-dwelling 'sandpeople' and Jawas, the film's main make-up, costume and creature designer went down with pneumonia brought on by the massive drop in temperatures in the desert at night. He was flown back to London where he was hospitalized for two weeks.

It was difficult to decide whether nature or technology was the production's worst enemy. The latter almost put pay to Kenny Baker one day. During filming at Luke Skywalker's home, the Lars farm, Baker had once more climbed into the belly of R2-D2. A collection of radio-controlled robots were also in the scene in which Luke and his uncle purchase two droids from the Jawas. (Baker's stage partner Jack Purvis was playing one of the Jawas, with Gary Kurtz's two daughters, Tiffany and Melissa, and five Tunisian children as the others.)

'It was the scene where we were showing off what we can do. I am wombling across the desert in my own sweet way. Suddenly Jack shouted to me, "Lookout Ken, there's a robot coming in,"' he remembered. Before he could react, a collision had sent Baker and his robot flying to the floor. 'It was not exactly the M1, you don't expect something to come ploughing into you in the middle of the desert. This other robot careered into me at about twenty miles an hour and knocked me sideways. He had gone out of control.'

Renegade robots became a regular threat to Baker's livelihood. 'Nobody could really control them,' he laughed. 'The radio signals would get mixed up with whatever else was flying around and sometimes they would go a bit haywire.'

There were successes in the desert, however. Mark Hamill and Alec Guinness struck up a rapport that worked well on screen. Hamill's playful sense of humour had endeared him to Sir Alec and his wife on the very first day of filming. Lady Guinness, travelling with her husband, had been relieving the boredom by sketching the Tunisian scenery and had laid out her canvas near an ornate mosque. Within minutes of settling down to capture the scene, however, an irate local had run over to her, grabbed her sketch and torn it to shreds. Guinness and his wife, surprisingly oblivious to the fact it was forbidden to photograph or draw any religious buildings in the country, turned to Hamill for an explanation.

'What did she do?' Guinness asked Hamill.

'He was probably just the local art critic,' Hamill replied to Guinness's delight.

Of all the memorable sights she witnessed on Star Wars, none tickled Bunny Alsup as much as that when Sir Alec prepared for his first scene as Obi-Wan. Lucas, Kurtz and the crew looked on in bemusement as the great knight of the stage lay down on the desert floor. 'He laid down on the sand and rolled around to get his costume looking dusty and dirty,' smiled Alsup.

Hamill had been given little instruction by Lucas before the first day's filming, but that was hardly surprising since, in essence, he had hired the leading trio to play themselves. Hamill's only clue came when, during an early take, he tried imitating his insular, soft-spoken director. 'I did it just like I thought George would react in the scene,' said Hamill, who had expected a rebuke. Instead Lucas muttered: 'Cut. Perfect.'

'I was flabbergasted. I thought, "Oh, I see, of course, Luke is George."' For the remainder of the film Hamill was as relieved as he was mildly unsettled. 'I began to really feel like I was playing George.'

Despite the early setbacks, Kurtz saw his waiting Hercules into the north African skies on time after a dozen days. For Lucas, however, there was plenty to indulge his pessimistic streak. He left Tunisia knowing many of his shots of R2-D2 and the landspeeder had been a disaster. A giant 'bantha', a shaggy, mammoth-like creature ridden by the sand people, had also been unusable. He knew both would have to be reshot, probably in California.

Already behind with his shooting and with serious doubts about his film's technology, Lucas left Tunisia more worried than when he had arrived. Shortly before climbing on the jet out of Africa, Lucas sent Marcia a postcard. It read: 'Are you sure Orson Welles started this way?'

Extract taken without permission from: Empire Building by Garry Jenkins, Simon & Schuster Ltd, 1997. ISBN 0-684-82092-7