A New Way to Please You, RSC Swan, Stratford-upon-Avon

Comedy normally sides with youth against age.

Comedy normally sides with youth against age. In a rich strand of this genre, parents and oldsters are largely presented as the repressive and often corrupt obstacles to the younger generation's desire for a true love that transcends considerations of wealth, dynasty and narrow self-interest. That arrangement is bracingly up-ended in The Old Law, a black Jacobean tragicomedy written by Middleton and Rowley in 1618, and presented now in the Royal Shakespeare Company's Gunpowder season; renamed with its original subtitle, A New Way to Please You.

The piece imagines a dystopian state where, for ruthlessly utilitarian ends, a new edict decrees that men will automatically be executed when they reach the age of 80 (their usefulness to the country deemed to be defunct) and women, once their childbearing and rearing days are over, will be accorded the same statutory treatment at 60. It's not so much euthanasia, as a cold, compulsory culling.

The play's Neverland-style, classical location is designed to camouflage, but not to disguise, some close-to-home Jacobean anxieties about rulers who feel that they can abuse their prerogative by inventing laws simply to suit their turn.

Though it could use a bit more wildness and astringency, Sean Holmes' shrewd, entertaining production liberates the topsy-turvy energies of the piece by giving the piece a generalised, modern setting. Seventies glam rock is the preferred sartorial style of the calculating, cowardly, young swine, who can't wait to get their hands on the parental wealth in order to blow it all on fashionable retro-clobber. Their ringleader is Simonides, played with an arresting, tart-with-no-heart pertness and with transparent bad faith oozing from his Northern Irish cadences by the very talented Jonjo O'Neill.

In this Liquorice Allsort-coloured world, unedifying practices abound as a result of the new edict. Funerals and weddings clash as husbands strive to marry dolly birds the moment their poor, old spouse gets the chop. Birth certificates are deviously doctored. To prove their viability, the ageing engage in contests with their juniors. As a result of the eugenic weeding, worthless young men are fast-tracked to the judicial bench.

The official line in this society is that to be a good son is the same as being a good subject, for a King is a father to his people. But there's a painful, inherent contradiction in a piece where the monarch appears to sanction the impiety of state-assisted parricide. Not that the enigmatic ruler here is all that he seems; and the production could do more to give him a visually sharper relationship with his experimental creation.

I doubt if this play will become a fixture in the repertoire, but Holmes' production, at once highly diverting and disturbing, establishes it as much more than a cranky curiosity.

To 3 November (0870 609 1110)