That river is the Narmada, beloved of Kipling, the holy waterway that divides India into north and south. In Hinduism, a "sutra" is a collection of moral sayings (as in Kama Sutra). So A River Sutra's title suggests it's a work of spiritual instruction as well as a play. The character in need of guidance is a former bureaucrat (Sam Dastor), who has left the city to run a guesthouse and contemplate the spiritual life in the country. Only in the broadest sense could you call him the hero. Instead, he's the play's fall-guy, an ineffectual navel-gazer, whose romanticised quest for enlightenment is hamstrung by his sense of his own importance. From his house above the river, he's in a perfect place to bump into ascetics on pilgrimage, or to pop into the local mosque, where his friend Tariq Miah (Talat Hussaim) dishes out gnomic advice. Yet the Civil Servant never gives off the impression that his new-found spirituality is more than a retirement hobby, classier than gardening or stamp-collecting, a kind of DIY of the soul.
Not that the play requires him to do much, except listen. The action proceeds through the stories people tell him, which are acted out for the audience. A Jainist monk tells how his father spent 72 million rupees helping him to renounce the world. Tariq tells of a boy with a voice so beautiful it leads him to his death. An ugly musician is married by her father to music itself, and a dreadlocked holy man (Sotigu Kouyate, amazingly spindly and utterly imposing) steals a girl from a brothel. What binds these tales together, with the loosest of ties, is the theme of love, in its various forms. As Tariq says, "The human heart has only one secret: the capacity to love."
With such a large venue, and a relatively small cast of 11 to fill it, it's a credit to Indhu Rubasingham's direction and Tina MacHugh's lighting that the stage never feels empty and the eye is never in doubt which way to look. But, if the acting expands to fill the space, you can't say that of the story (adapted by Tanika Gupta from Gita Mehta's novel), which falls a couple of swords short of its epic aspirations. Blame that partly on A River Sutra's length: two and a quarter hours simply isn't long enough for anything but the most superficial of spiritual journeys. Nor does it give the play's central symbol of the river time to seep into the imagination. But blame it mostly on the play's portmanteau structure. Its parts greater than the sum, it tempts the audience with the promise of Eastern mysticism, but delivers little more than the commonplace that to love other people is important and that the divine is all around us. The Civil Servant looked a little deflated to discover it was all that simple. Me, too.
To 4 Oct, Three Mills Lane, London E3 (booking: 0171-928 2252)