Robin Soans is an angry man. He's angry about the Iraq War. He's angry about Simon Cowell. He's even angry about toothpaste.

They're all symptoms of capitalism's worst excesses (well maybe not toothpaste, but we'll get to that later), he says, discussing his latest play Perseverance Drive.

It's not big industry which bears the brunt of his bile, however, but what he describes as the feeble, divided opposition coming from the left.

What this has to do with a drama about a family being torn apart following the death of its matriarch only becomes clear when he explains the pay's genesis.

"I was in Mississippi on a fact-finding mission for another play and I went to a number of church services, where two things struck me," he says.

"By encouraging the congregation to put up and shut up in this life because they'll get their reward in the next they seemed to be politically stultifying the African American movement.

"But at the same time the church was a fantastic inspiration for people to carry on their lives with real determination."

That dichotomy was the seed for the play, which was germinated when Soans met a fan back home who told him about about the conflicts within his own family.

"It struck me that here was an intelligent, faithful and well-meaning family which had somehow ended up at loggerheads," he said.

Their story proved the inspiration for a family drama spanning five years, beginning with a funeral in the Caribbean and ending with a highly charged gathering around a London dinner table.

The familial tensions on stage are emblematic of the Church's own schisms, says Soans, but also of the deep divisions hampering those on the left.

"When you see the worst excesses of capitalism you can't help but think why is religion, certainly in this country, so feeble when it comes to opposing them," he says.

"The Church should be fighting for the principles on which it was founded. Christ was a militant, who  turned over the tables of the money changers in the temple, but all you get today are a few squibs of half-hearted philosophy from the odd bishop about how we should be doing more to help the poor.

"The whole opposition to rampant capitalism and the celebrity culture embodied by Simon Cowell is very split.

"If the voices of two-and-a-quarter million people marching against the Iraq War could be silenced because capitalism said it wanted a war you do start to wonder if anything you do makes a difference.

"It's like if everybody squeezes a little more toothpaste from the tube the manufacturers will just put the price up, so what's the point?"

Despite his mild-mannered rant, he believes enough in his power to make a difference to have written the play, which he hopes will 'impinge on somebody's conscience'.

It's not just about politics, either. Soans is proud to have written a rollicking family drama with an all-black cast in which the issue of race is barely touched upon, something he says is all too rare.

Nor is it a pessimistic or mirthless play, he insists, but one which discusses weighty issues like family and faith, while offering a glimpse of a 'different life'.

Or to put it more bluntly, in Soans' words: "It's not just another play about two boys masturbating in a shed in Wembley. It's a big, messy family saga."

* Perseverance Drive is at the Bush Theatre, in Uxbridge Road, Shepherd's Bush, from July 4 to August 16. For tickets, visit www.bushtheatre.co.uk or call the box office on 020 8743 5050.