George Bernard Shaw will always have a special resonance at the theatre originally dedicated to his work, and here is a play which not only features Shaw as a character but has other connections with the area.

Two friends with whom Shaw corresponded over a period of nearly half a century were Sir Sydney Cockerell, curator of the Fitzwilliam Museum in Cambridge, and Dame Laurentia McLachlan, Abbess of the Benedictine Abbey at Stanbrook, Worcestershire.

Hugh Whitemore has cut and pasted their letters and diaries to paint a picture of three interconnected lives, cleverly using a particular incident to leave the audience in puzzled suspense over the interval.

It's a gentle, reflective if not particularly exciting evening which gives an intermittently interesting perspective on intellectual life in early 20th century Britain. You get to see three very good actors - Roy Dotrice, Patricia Routledge and Michael Pennington - ageing gracefully.

Roy Dotrice's performance as Shaw is the real gem. I don't know how far he may have researched it from newsreels, but it is uncannily persuasive as the impish playwright gradually matures from sprightly tango dancer to decrepit age.

Despite the longeurs of his plays, as a personality Shaw could never be less than entertaining: his comment on being considered for the Nobel Prize ("I can forgive Alfred Nobel for inventing dynamite, but only the Devil in human form could have invented the Nobel Prize") is just one example.

The problem is that neither Cockerell - a rather self-deprecatory personality, despite his real achievements in establishing modern standards of museum display - nor Dame Laurentia are nearly as interesting.

Cockerell did have an extraordinary range of better-known acquaintances, though: he was present at William Morris's death, met Tolstoy and introduced Lawrence of Arabia to the Shaws.

Still, it makes for a pleasant enough evening and Simon Higlett's set - a lavish Arts & Crafts room with Morris wallpaper and lots of PreRaphaelite images which anoraks can have fun identifying - is a real collector's item. You couldn't imagine anything further removed from the the urban wasteland he recently designed for the Rep's Promises and Lies.

* Running time: Two hours, 35 minutes. Until Saturday.

Terry Grimley