Christian characters, especially vicars, in movies or TV shows are normally one of two types. The first type is the stupid Christian. They respond to questions about their faith in a way that suggests that they have never had to deal with hard questions before. When suffering comes, or evidence that challenges the Bible or their ethics, their faith is completely shattered. In the end, they rebuild their faith with a more liberal version of what they understood before.

The second type of TV Christian is the angry man who responds to questions with rage or fury. He's probably an American fire-and-brimstone preacher whose wife is terrified of him. There are hints of physical abuse. To this character, all questions and challenges are inherently bad. All disagreement must be shut down. This guy is usually the baddie, although perhaps crumbles at the end, or is redeemed in some way, like Shaw Moore in Footloose.

There are more types, I'm sure, but the point is this: Christian characters on TV tend not be measured, reasonable, good-humoured and intelligent all at the same time. Like the Christians that I know. And try to be myself.

After witnessing this state of affairs for a few years I could see that if wanted to watch a reasonable, good-humoured debate about science and faith, for example, I'd have to write it myself. So I did. The result was a play called The God Particle.

In this play, I wanted to create an atmosphere in which a skeptical scientist fired numerous questions at a Christian who has some good answers, as well as posing a few questions of his own.

But a play can't simply be a scripted debate. There need to be characters and a story to take you through. The resulting play is an unusual blend of romantic comedy and science fiction, which takes place in a curiously named village of Threepiggs, home to an Institute of Advanced Quantum Theory.

The new vicar, Rev Dr Gilbert Romans, arrives and is keen to track down his predecessor, Father Steel, who has strangely disappeared. He is joined on this journey by Dr Bex Kenworthy, a quantum physicist. She is not only skeptical about all things religious, she doesn't know any people of faith. Gilbert, then, is a real curiosity for her. Despite their differences, Gilbert and Rebecca discover they have an awful lot to talk about.

One of the key themes of the play is what it means to have an open mind. The GK Chesterton quotation comes up: "The purpose of having a mind is the same as having an open mouth - to close it on something solid." In the play, Bex argues that a good scientist would never close their mind on anything, but Gilbert wonders whether Bex has closed her mind on the scientific process.

The play went through a number of drafts in which the tone of the conversation was honed and the arguments edited. A number of passages that felt too 'preachy' were removed as I was keen to make the debate between the characters as even-handed as possible. Both sides need to feel their questions are being asked and answered in some way so that any one is comfortable watching the play and no-one feels 'targeted'. The feedback on the play has been very positive. Live audiences really engage with the story, the characters and the issues being discussed.

The downsides of a play, however, are the costs and practicalities of live performance. Actors have to show up, as do audiences. Tours can be grueling, especially when they involve erecting and taking down lights, and driving long distances. The play itself is the tip of the iceberg.

But now the play has found new life by being turned into a DVD. I was keen for the DVD to capture the theatre experience. So the play was recorded in May in front of a live audience at the Merlin Theatre in Frome by Luke Aylen and his team at Kairos Film and Media. And the finished product is finally available so you can judge for yourself whether it is Gilbert or Bex who have an open mind.

The God Particle is available from the Good Book Company, and more information can be found here.

James Cary is a comedy writer for BBC TV and Radio. He has co-written Miranda (BBC1), Bluestone 42 (BBC3), and Another Case of Milton Jones (BBC Radio 4).