If you look at the stills from Jamie Stone’s film Fritz, they look like something Terry Gilliam would create. Stone’s image of an ancient soldier with bushy eyebrows, enormous grey beard and military helmet could be straight out of Time Bandits or The Brothers Grimm.

The difference is that, where Gilliam has a reputation for troubled and expensive projects — The Adventures of Baron Munchausen cost $46m (£24m), twice the original budget — Stone’s film came in with change from £200.

Yet the 20-year-old’s low-budget debut was deemed good enough for selection by the Edinburgh International Film Festival, where it was part of the sell-out Scottish Shorts package.

It was a remarkable achievement for Stone, a second-year student at Edinburgh College of Art, who shot the whole thing in 1½ days in his parents’ house, casting his 10-year-old brother, Magnus, in a starring role.

“One of my tutors was walking past the editing suite when I was showing a friend a rough cut,” says Stone, from Torrance, East Dunbartonshire. “She liked it and said she’d send it away with a couple of the graduation films on the off-chance it might get into the film festival. I was really surprised when they didn’t go for the graduation films, but went for mine.”

Despite being the cheapest film in the two-week event, the seven-minute comedy short was warmly greeted by audiences. It tells the story of Fritz, a 90-year-old German spy for whom the second world war has never ended. Hidden in his bunker deep within enemy territory, he transmits coded messages, “frogspawn . . . teapot . . . dandruff”, uncertain of where he is, or even in what era.

Meanwhile, Tom, a petrified 10-year-old boy in the bed above the bunker, is intercepting his transmissions. “They’re both too afraid to find out who the other one is,” says Stone. “They can hear each other, but both assume it to be something else.”

His aim was to make a “live-action cartoon” and Terry Gilliam was foremost in his mind. “If I had to cite an influence it would be his visual style. I gave my art director a copy of Lost in La Mancha ’s failed attempt to make a film about Don Quixote so she could make the colours underneath the bed look like his. But we’re much cheaper than him.”

To raise the money, the crew threw in £20 each, while young Magnus contributed his toys as props. Finding himself short of cash while giving his brother’s friends a lift home from school, Stone was reduced to borrowing money from them.

“Most of the budget went on props, which were the most important thing for setting up the world of the story, especially underneath the bed,” he says. “There’s a scene at the end where the German peeps up and sees all this crazy stuff in the bedroom and then decides the boy doesn’t exist. I really wanted a Furby (an electronic soft toy) for this, so I had to take a collection from all the kids in the car to buy it in a petrol station.”

They kept costs down by filming everything in Magnus’s bedroom and letting the cast and crew stay the night. They kipped on the living-room floor — apart from the cameraman, who was banished to another room for snoring. “It didn’t cause any more disruption than usual,” he says. “The house is usually pretty hectic.”

The eldest of five, Stone disregarded the adage about never working with children and cast Magnus as Tom. “He took a little persuading, but he was very happy when it actually came to shooting,” Stone says. “He was very natural in front of the camera because he was in his own home, and he was quick to do what I asked. I couldn’t have been happier with his performance and when he was on the big screen, he lapped it up like a movie star.”

With the film in the can, Stone approached a musician friend, Ink Wilson, a member of the 12-piece Glasgow band How to Swim, to compose a pace-setting soundtrack. “It pushed the production values up,” says Stone. “As soon as we put his music to the film, it made it look as if we’d spent a lot more money.”

Conceived and made within three months as part of a college assignment, Fritz might easily have gone the way of many a student project and never been seen again. Instead, Stone found his work being screened alongside films by graduates, a Scottish Bafta winner and one of his own tutors. “It held up all right,” he says with pride. “Now all the fourth-years hate me.”

He resisted the temptation to network with the industry people — he is, after all, only a second-year student — but made full use of his festival pass, clocking up as many as seven films a day. The exposure to so much quality cinema would be a godsend for any impoverished film student, and Stone is now eager to get back to college and start work on new scripts, as well as moonlighting on a pop video for a friend’s band in Sheffield.

He’d like to direct professionally, but whatever he does next, the experience of filming Fritz will stay with him. “I’ve learnt an immense amount because every step of the way has been something new,” he says.

“I especially learnt the benefit of planning: we were able to do everything on such a small budget because we’d planned in such detail. We rattled through the shots, which made the shoot shorter and the costs less. And scarily, it turned out just as I’d imagined — right down to the colours.”

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