It is 1809, and in a room overlooking the garden at Sidley Park - a large estate in Derbyshire - tutor Septimus Hodge is teaching his pupil Thomasina Coverly, a young prodigy whose grasp of chaos theory and fractals is centuries ahead of her time. Outside, the formal classical gardens are being turned into a sea of mud as a minor Capability Brown is intent on transforming the landscape into a picturesque idyll complete with hermitage. Only he hasn't provided the hermit to go in it, much to the disgust of Lady Croom.
Fast forward to the present day and in the same airy garden room (design by Stephen Brimson Lewis) historian Hannah Jarvis is researching the hermit of Sidley Park. The plot thickens with the arrival of academic Bernard Nightingale, whose own theory links Lord Byron to Sidley and a duel that may, or may not, have taken place there in 1809.
On the whole I can take or leave the plays of Tom Stoppard. This 1992 play, however, is a thing of such infinite beauty and dazzling complexity that I could sit and watch it for 365 days on the trot and never get bored. It combines the most extraordinary and probing intellectual curiosity with an unguarded heart as the protagonists' stories, past and present, are woven together in a dance of time as the world grows cold.
This is not Stoppard as show off, but a mature Stoppard entirely intellectually and emotionally engaged, and the play fizzes with excitement, sex, uncertainty and tragedy as a result. Rachel Kavanaugh's production is the best work she has done for a long time, and there are performances to cherish, particularly Amanda Harris's as the imperious, flirty Lady Croom, Hermione Gulliford as the feminist Hannah, who is reluctantly drawn into the dance, and John Hodgkinson as the shameless media-hungry don.
· Until October 16. Box office: 0117-987 7877