A LECTURER, Henry Brook (Alan Davies), is both intrigued and attracted by his brilliant student Edie (Leila Mimmack). She believes that she can use quantum theory to prove the existence of God. Together, they write a book about the explicability of biblical miracles in a cosmos of infinite possibility. It becomes a publishing phenomenon. For Henry, the book is a playful scientific exploration; for Edie, it is deadly serious. It inspires a Church, which spirals into an international cult in which God is worshipped through physics. The book gives its title to David Baddiel’s début play God’s Dice.

Henry is dismayed by the adulation that he attracts in the Church, which entirely misrepresents his views. His appalled wife, Virginia (Alexandra Gilbreath), a world famous proponent of atheism, becomes the target of death threats. As the marriage falters, an old friend Tim (Nitin Ganatra) complicates the relationships with his predatory sexual attitudes. As you may have guessed, it doesn’t end well for anyone.

God’s Dice has been burdened with the worst reviews for a major new play this year. So let’s offer up some positives that the critics have been overlooking. It’s a fascinating idea, it has some cracking jokes, it’s acted with great conviction, and the video design of whirling fractals and equations is a delight (Ash Woodward).

So what’s gone wrong? For a start, there is not a single believable character. They are all vehicles for ideas, and their dialogue is made up of ideological disputes. Edie is a Christian. Is she the kind of Christian who says her prayers, attends church, and works on behalf of the poor? Of course she isn’t. She’s the kind of Christian who has evil intentions and murderous inclinations — the kind who, if dark television dramas are to be believed, make up most of the electoral roll. It is lazy and depressing characterisation.

Then there are the clichés. A middle-aged man watches in wonder while someone half his age scribbles mathematical equations on a whiteboard, overturning everything that he thought he knew. His wife is desperately late for her aeroplane flight, but finds time to keep the taxi waiting as she argues about religion. A lecturer turns out to be the college lothario, lamenting that the days are gone in which sleeping with students was one of the job’s perks.

Churning under the debates about faith and science are themes of the potential of social media to foster hatred, the harassment of professional women, and the impact of midlife crisis on men. The lack of focus makes the pace drag. In the place of resolution, there is a ludicrous, melodramatic climax.

Christian themes have been taken surprisingly seriously in the past year of theatre — from the grieving of Natasha Gordon’s Nine Night (National Theatre and Trafalgar Studios), through the neighbourliness of Come From Away (Arts, 5 April), to the visions of Our Lady of Kibeho (Arts, 11 October). God’s Dice has heartfelt intentions, but doesn’t come close to feeding the soul in the same way.

God’s Dice continues at the Soho Theatre, London, until 30 November. Tickets from www.sohotheatre.com or phone 020 7478 0100.