Perhaps the greatest strength of The Winter Guest, Sharman Macdonald's beautiful, elliptical new play, is that she has the courage to stage the inconsequential and show how it reveals our great preoccupations. There is no plot as such, just a series of duets between eight characters, who often talk away about nothing very much. But as the play progresses, she adds a little shading here, a little depth there, until the last line reveals the overall shape, and what looked deceptively formless suddenly has meaning.

On one level her play (first seen at West Yorkshire Playhouse) is about relationships. Macdonald picks several couples - a mother and her widowed daughter, a budding adolescent romance, two elderly lady companions, a pair of schoolboys - all of whom are rattling round a beach on the west coast of Scotland on a freezing February day, all of whom are on the verge of some massive change in life. As they alternately scold and hold each other, she puts across wonderfully the conflicting needs to be needed and to be alone. But the plays' deepest theme is death, and the presence of death in life.

Death is the unseen companion of everyone in the piece - a winter guest anticipated by the old ladies. It has frozen the life of the young widow and cast a shadow over her son. And even as he struggles to break the ice that have formed over their lives, the unwelcome guest steals in elsewhere. Yet the mood of the piece is not sombre and the elegiac note that seeps into every nook of the play is counterbalanced by its warmth and robust humour.

Alan Rickman's sensitive, generous production does it wonderful justice. It has a natural ease that convinces you that you are simply eavesdropping on the characters and it brings out both the play's fragility and its earthy humour. Rickman is helped by Robin Don's beautiful, atmospheric set, which plays cleverly with perspective to portray a long promenade beside an icy sea, reflecting physically the play's preoccupation with life at the edge of death.

Macdonald writes with wit and compassion about the texture of relationships and the fine cast rises to this with relish. Phyllida Law and Sian Thomas are excellent as the eccentric mother and defensive daughter, trying desperately to reach each other but constantly foxed by their sharp tongues. Sheila Reid and Sandra Voe are delightful as the two old ladies. who try to head off the Grim Reaper and fill time with a hectic schedule of cremations and cream teas. John Wark and Anthony J. O'Donnell are immensely funny as the two truant schoolboys, fretting about puberty and experimenting with remedies to increase their sexual equipment.