How did they do it? Jemma Walton found out.

By day Peter Darnes and Phil Knight were a tax inspector and an engineer. But in their spare time they were giving Steven Spielberg a run for his money.

Because, like many of us, the two of them thought it would be nice to make a film. But, unlike many of us, they actually had the creative flair and the dogged determination to actually make one.

They have spent their Saturday evenings making butties for cast and crew members and had to colour their leading man's hair with black felt-tip pen after he dyed his barnet blonde, but they have got there in the end.

The result is Christine Piper, a fantastic take on obsessive love shot through with pitch-black humour, filmed on location not in Los Angeles, London or Paris, but in sunny old Peterborough.

"We can't look at it objectively because we're too close to it," said Phil, the writer and director.

"We sat through a screening in Salford, and there was a blip in the sound and we both flinched, but we looked around and no one else in the audience had noticed.

"When we watch it, we just see all the little things that are wrong with it."

Christine Piper follows the character Christine as she stalks the manager of her local supermarket, and decides that he loves her as passionately as she loves him. (He doesn't.)

Christine eventually decides to kill a pretty young lady the manager is friends with at work, but doesn't quite manage it. Sounds nasty, but Christine and everyone else end the film living happily ever after.

"We think it will appeal to anyone that's ever been in a failed relationship," said Peter, the producer. "Or who knows someone who's been in a failed relationship, or for anyone obsessed with someone, or who knows someone who's obsessed with someone. Which is pretty much everyone!"

The two met while doing "normal alternative"-style standup in clubs such as Gaslight, which used to be over the Solstice.

They played a lot of gigs in London as well, until the point came where they had to decide to give up the day jobs and make a serious go of it, or concentrate on their day jobs.

They decided that their jobs paid too well for them to take a punt on a career in comedy, and that was that – or so they thought.

Peter (42), from Market Deeping, concentrated on his job as a tax inspector, while Phil (38) from Netherton, balanced work with writing TV and film scripts.

Eventually, Phil got an interview with Celador, the makers of Who Wants to Be a Millionaire, who wanted him to cut his writing teeth on the radio.

"But I didn't want to do that," he said. "And so I went back to doing my own thing."

Phil asked his old pal if he remembered a script called Christine Piper, and Peter said he did, and Phil asked him if he would like to help him turn it into a film and Peter said he would.

And here they are, trying to sell it to a film distributor.