Oedipus Rex/Oedipus at the Crossroads, Rosemary Branch Theatre, London

Talk about being dealt a bad hand. Fate has rarely selected a worse set of cards than the one it shuffled in the direction of Oedipus. The oracle predicts at his birth that he will kill his father and marry his mother. To try to outwit this divine prognostication, his papa has him put out to die, his baby feet riveted so he cannot crawl away. Best foot forward, Oedipus. You could scarcely think of a more tactless injunction. For the way forward is also the way downwards into horror. Luck allows him to survive only so that, at the zenith of his kingship, he can, with deadly irony, become the detective who uncovers that he himself is the criminal who has brought the plague to Thebes. Son and husband to a wife who kills herself, he gouges out his eyes in shame so he cannot see the children to whom he is brother and father.

It's clear that this story outrages Jeremy Kingston, an excellent writer who also happens to be a theatre critic colleague. But instead of getting self-righteous about it, Kingston, in Oedipus at the Crossroads, has written a deliciously witty dramatic riposte to Sophocles's original. The two plays – the ancient Greek original and the revisionist riff – can be seen together in a highly diverting diptych. Directed by Robert Gillespie on a low-to-no budget, both plays are performed by a cast who move with relish from the screw-tightening solemnity of the tragedy to the barbed levity of the comic counterblast.

Oedipus at the Crossroads is located at that moment in the back-story of the tragedy when Oedipus (Alex Hughes), fresh from hearing a second oracle, is nearly run down by an angry old man in a chariot. In slaying him, Oedipus unwittingly kills his father Laius. Kingston subversively rewrites the myth. Here, it's Laius's catamite soldier who gets killed. As the vengeful monarch makes to murder Oedipus, the young man blurts out that his early death will at least disprove the divine prediction about parricide and incest. Laius twigs that this must be his son. What follows is firstly a hilarious impasse between a rebellious young hero who would like to prove that oracles are superstition and the now-pious old king whose crusty religious beliefs are put to a tricky test. If oracles are true, then he will have to die at the hands of this intimate, but unwilling stranger.

The play slowly reveals that Oedipus's fate has been stage-managed by a corrupt clergy to win people back to superstition. I won't give away the ending, except to say it is outrageous and perfect. Not so much "A Funny Thing Happened on the Way to the Forum" as "A Twisted Thing Happened on the Way to the Agora", this is a double-bill of singular delight.

To 23 Feb (020-7704 6665)