THEATRE Blue Murder, Quakers Friars

Through the long windows, a beefy guardsman can be see parading up and down, while from a radio newsflash, we learn that yesterday the Abortion Bill cleared its first reading and that Chancellor Callaghan has resigned in the wake of devaluation. After checking that no one can see him, the guardsman clambers inside, enjoys a brisk, passionate snog with the besuited ex-wing commander in situ, tries to put the squeeze on him for 50 quid to help a girl he's landed in the family way and then has to hide himself in the loo when another mandarin figure enters to make a clandestine telephone call to a journalist, offering him the scoop that the PM is a Communist agent.

All par for the course, you might think, in a Whitehall farce. The adroit twist is that these shady shenanigans occur in the Lord Chamberlain's office in St James's Palace. Home of the theatrical censor at this date, it's a place with more need than most to be seen to be above reproach, given that if such events had been presented here in a playscript, the blue pencil would have run out of lead. In A Game of Soldiers, there's further piquant complication in the fact that Foreign Bodies, the play which has been brought into the office for some vigorous delousing, is the one we have just seen before the interval.

A comedy in which the street values of early Sixties Soho attempt to invade the chintzy, kinks-under-the-carpet of the Shrewsbury bourgeoisie, Foreign Bodies - like its partner play - develops a loopy Pirandelloesque self-consciousness. In both, a young uptight middle-class dramatist seems to be penning the proceedings of which he is part. Together, these works make up Peter Nichols's exhilaratingly funny Blue Murder, premiered now in the author's very well acted staging for Show of Strength at Bristol.

Nichols is more famous at the moment for being unproduced and loquaciously bitter about it than for being one of our most penetrating and virtuosic post-war playwrights. From the above, you might get the impression that Blue Murder was just something he'd dusted down from his bottom drawer, a piece redundantly remounting defunct battles. That reckons without the nifty use he makes here of hindsight, as the Sixties characters hazard an approximate forecast about a future we're actually living. "They'll be banning the Black and White Minstrels next," splutters Andrew Hilton's hilarious mandarin incredulously on hearing that there are grounds for objecting to the title Ten Little Niggers. Censorship then and pc now are brought, at such moments, into thought- provoking proximity. Through his fictional playwright, Nichols's recurring theme that captivity within limits is more enabling than the dictatorship of uncertainty is aired again, though the huge difference between constraints on form and on content gets rather blurred. Seriousness and high-spirited silliness operate together beautifully in the best bits of Blue Murder and the jokes are classic.

Booking: 0117 953 7735 to 25 Nov