Best of Friends, Hampstead, London

An old-fashioned, civilized evening

The director is James Roose-Evans, the veteran founder of Hampstead Theatre. Michael Pennington's silver-haired, fondly reminiscing Cockerell sits in the same room as Roy Dotrice's bushy-bearded Shaw and Patricia Routledge's serene and chortling, bewimpled McLachlan. This is a cluttered vintage study - all dark wood, and William Morris wallpaper - and they mainly perch at separate tables. Occasionally, the pen pals turn to make smiling eye contact or trundle over to sit nearer one another, maybe pouring tea or polishing an apple as the Abbess speaks of sending a harvest basket to Cockerell. Actually, one could do without some of the sound and lighting effects - from chuffing train noises to sweeping WWII searchlights - which are clearly meant to add more animation to the evening.

Nevertheless, what's remarkable and rather wonderful is how their company grows on you, with a humour and wisdom which becomes very touching. In fact, Best Of Friends manages to be both stuffy and oddly refreshing, precisely because it is anti-dramatic and very civilized in an old-fashioned way.

The letters' mix of informality and eloquence is often a joy. There is some food for thought in their debates about the nature of faith, true freedom and open-mindedness. Shaw's teasing wit surfaces delightfully too, making you really wish you'd known him - which is more than one can say for some of his plays. He also reveals intriguing ambivalences, asking the nuns to pray for him yet pushing his luck destructively - to breaking point - by presenting McLachlan with a copy of his book, Adventures Of The Black Girl In Her Search For God, which she deemed blasphemous. Her refusal to forgive him for a long time is faintly disturbing. Meanwhile Cockerell - who, like Shaw, had an invalid wife - expresses his deep fondness for the Abbess in near-marital language which is curiously sad, joyful and Platonic too. An ultimately rewarding evening, for all its faults.

To 1 April, 020 7722 9301

k.bassett@independent.co.uk