IN drama one looks for a collision between forces of equal weight or the exploration of a moral dilemma. William Nicholson's Shadowlands at The Queen's has many qualities, including a compassionate grace, but it deals with love rather than conflict and spiritual pain rather than the clash of ideas.

Based on Mr Nicholson's own very good 1985 television play, it is about the late-developing love betweeh C.S. Lewis and a fervent American admirer, Joy Davidman. Lewis, a great critic, Christian apologist and chlldren's author, is seen as com fortably cocooned in a world of donnish celibacy. Into his charmed Oxford life steps Ms Davidman, a sometime poetess whose rocky marriage has produced a young son. She divorces, settles in Oxford, goes through a technical marriage with Lewis to secure her British citizenship. Then, when she is suffering from terminal bone-cancer, Lewis discovers that he is poleaxed by a genuine, committed love and re-marries her in the eyes of God.

It is obviously a moving story but not an inherently dramatic one. On television, with its ability to evoke place and period, this did not matter. But, in the theatre one looks both for tension and conflict. It is true we get some fairly routine High Table banter between Lewis and his Magdalen colleagues. There is also a sparky moment when the new Mrs Lewis challenges her busband's assumptions about education. But, on the whole, this is a story of love fulfilled; which is admirable in life but stubbornly undramatic.

What drama there is stems from Lewis's own spiritual crisis. At the beginning he is seen arguing that "suffering is God's love in action." But" the death of hls wife makes him question his Christian faith before learning to accept that pain and happiness. are indivlsible. That is all very well but, in the theatre, one is more interested in dilemmas than in their resolutions. The problem with Lewis as a dramatic hero is that he never seems plagued by moral choice. On the one occasion he might have been (on the question of how this champion of the sacramental view of marriage could wed a divorcee) he resorts to a neat bit of intellectual double-think.

I was,in short, quietly moved but never intellectually stirred; and Mr Nicholson's attempts to inject "theatricality" into the proceedings are too blatant to be really convincing. At various points Ms Davidman's bookish son enters through a wardrobe into the magic land of Lewis's Narnia. But, although Elijah Moshlnsky stages these episodes well, as if they were like the sudden access of Spring in the first act of Die Walkure, they lack any real internal logic.

The best thing about the evening is the acting. Nigel Hawthorne does not naturally possess the ruddy-complexioned, country-farmer look of the real C.S. Lewis but he is excellent at conveying the faint embarrassment of an intellectual surprised by passion. He is forever staring at his shoes, twitching his raincoat, thrusting his hands deep in to his pockets as if taking evasive action against the promptings of his heart. He is also very good in his snappish, inconsolable desolation immediately after his wife's death. Mr Hawthorne does all an actor can do; but there is something about Lewis's capacity to adjust to the need for suffering that robs the character himself of tragic status.

Jane Lapotaire Is also watchably Impressive as Joy. Less instantly glamorous than Claire Bloom in the TV version, she makes her at first the kind of bustling, over-eager woman who dogs the footsteps of literary celebrlties. But Ms Lapotalre also endows her with a slightly truculent charm and a genuine sense of happiness at the fulfilment of marriage. Geoffrey Toone as Lewis's military brother and Philip Anthony as a querulous don also lend reliable support.

But I still feel it Is a story rather than a play, which is why it worked better in the narrative medium of teievision. It also never solves an eternal theatrical problem: that love frustrated, denied or delayed is dramatic but that love mutually fulfilled (as it is in the second act) leaves one envious rather than enthralled.