Jeremy Sams directs this notorious Sixties play-within-a-play based on the true stories surrounding the Marquis de Sade producing plays with the inhabitants of a lunatic asylum. The second production in the triumphantly redesigned Olivier, now a welcoming theatre in the round.

In preview, opens 14 May. In rep with Theatre de Complicite's beautiful The Caucasian Chalk Circle, National Theatre, London SE1 (0171-928 2252)

Forty Years On

The British Empire, family values and the old school tie are given the Alan Bennett treatment in this tremendously funny satirical tale of the century. Better timing for this revival could hardly be imagined.

From 12 May, Theatre Royal (01225 448844)

The Positive Hour

What is Emma doing with a man in a hood? Why is Miranda losing her patience with her new-man husband? April de Angelis's witty, astute play is a stimulating mix of men, money and S&M; Max Stafford-Clark's sharply acted production does it proud.

Tonight, Warwick Arts Centre (01203 524524); from 14 May, Palace Theatre, Watford (01923 810306)

The Rehearsal & The Double Inconstancy

More winning, imaginative programming from the revived Salisbury Playhouse with artistic director Jonathan Church directing two tart French comedies in tandem: Jeremy Sams's translation of The Rehearsal, a huge hit for the Almeida, and Marivaux's bittersweet The Double Inconstancy.

Salisbury Playhouse (01722 320333)

The Herbal Bed

A real-life 17th-century sex scandal involving Shakespeare's daughter in Peter Whelan's award-winning RSC thriller/love story, in town for a limited season. Stephen Boxer is outstanding as a cleric with a powerful lust for truth.

Duchess Theatre, London WC2 (0171 494 5075)

A Woman of No Importance

A chance to catch the least well known of Wilde's quartet of truly, deeply trivial comedies. Janet Brown stars.

Leicester Haymarket (0116 253 9797)