We heard the voice of God and it came from Yorkshire

RADIO

I took my son to the National Theatre. I was worried because, as it was a promenade performance, he would have to stand for hours and he was only four. In the event, he spoke only twice; once, in an urgent whisper, to ask whether Isaac was about to die, then, despairingly, to beg me to tell him it wasn't going to end. The mesmerising play was The Nativity, Tony Harrison's reworking of a Yorkshire mystery play, performed in strong, alliterative Middle English. No wonder Richard Eyre describes it as one of the greatest pieces of theatre he's ever seen, anywhere.

Eyre was reminiscing about this production during the first of Seven Stages (WS), an ambitious project to present the history of British theatre to the world. It has started well, with Michael Kay giving the background to the mystery cycles - religious dramas performed in the streets by urban guilds on the feast of Corpus Christi. In a Reithian blend of education and entertainment, shipwrights would present the Noah's Ark scene, bakers the Last Supper and nailmakers the Crucifixion. Brenda Blethyn, who played Mary at the National, recalled the extraordinary way in which agnostic scepticism was suspended in the face of the magnificence of the medieval world-vision, presided over by Brian Glover's benign and earthy God.

Adrian Henri's adaptation of Nativity to Judgement (WS) illustrated the genre. His style is different from Harrison's. In a brief hour, he tells the famous story largely by means of minor characters - a shepherd bringing a linnet to the manger; an elegiac chorus of bereaved Bethlehem mothers; Herod, sounding like an irascible mill-owner; horribly savage guards. When Paul Copley, as a worryingly wimpish Christ, cries out to his father in the Garden of Gethsemane, the reply from Heaven is blunt: "Son, ye're on yer own." Produced as a cross between old-time music hall and pantomime, it took time to establish itself; but suddenly, during the Harrowing of Hell, it came together and the magic began to work. The word "mystery" may well come from the old tradesmen's guilds, but mysterious indeed is the power these plays still exert.

And everywhere you go Jesus is watching you, from his vantage point on the hill. So begins Opera do Malandro (R3), which opened a season of Brazilian Words. Written during the military dictatorship of the 1970s, but set in the 1940s, Chico Buarque's play picks up where Brecht left off - even echoing Weill's music - for a samba re-working of The Beggar's Opera, this time in the company of the spivs, pimps and prostitutes of the Rio underworld.

Max, the hustler - or malandro - marries Teresinha, who comes from a comparatively respectable background. She wants to legalise his business, but he is steeped to the eyebrows in corruption. Relentlessly his enemies stake him out. Wriggle, threaten and bribe as he might, he cannot escape the snares his own past has laid for him. Strong, sinister and bleakly amusing, Malandro had such a world-weary timelessness that it was a shock when, towards the end, the news came that the Germans had lost at Stalingrad and Fascism was finished.

Document (R4) this week went back another year to the siege of Leningrad. You can rely on this series to unearth strange and interesting stories, as it did in the Leningrad archives. Despite Stalin's subsequent efforts to destroy all records of the siege, private diaries survive. They are agonising, often written at the very extremes of life itself, as the diarist's hand visibly weakens, falters and stops. Yet while people were starving by the thousand, one bird survived and is now on view, stuffed, in a tiny Leningrad museum. This dead parrot could sing and speak in several languages: its power to cheer its owner saved it from the pot. And Julian Putkowski discovered something else: throughout the siege, the radio station kept going. Between bulletins, they would broadcast a ticking metronome to remind the people that they were still, just about, alive.

Ten years later, Andris and Zsuzsi fell in love in Budapest. They were 14 and, had the Uprising not happened in 1956, they would have stayed together. In the event, they were separated - one went to England, one to Canada. Both married other people, both had children. Forty years on, one widowed, one divorced, they met again and, at last, were married. Sounding like teenagers still, they told their own story in Autumn Leaves (R4), a fittingly romantic tale for Valentine's Day.

And there was another in the evening. Iain Grant's A Case of Displacement (R3) was completely, brilliantly mad. A private eye tracks down, and falls for, a beautiful Polish philologist. Her great invention, a Typographical Replacement Beam, should have ended all the spelling difficulties of the world. Sadly, it goes into reverse and affects his brain. The script was like the random suggestions of an Amstrad spellcheck. "My refraction in the mirror looked like a copse ... I fell to the flood in a heat

Finally, a play that should have been listened to in the bath with the door locked and the phone off the hook. I was on the motorway and had to use a slip road to stop and concentrate. David Pownall's A Gift From the North (R4) was the old English sheepdog of shaggy-dog stories, in which four Lancashire whammelers (sic) catch a 45-stone sturgeon in a net and are persuaded that it belongs to the Queen. "Yon overgrown sardine" is entrained for London and there ensue rococo curlicues of plot, involving an incident in the Crimean War, a hot-air balloon, bags of flour, a lay preacher and a wooden leg bursting into flower in a Cheshire field, to the astonished delight of the farmer who takes it as a promising sign. Brian Glover, still sounding like God, was chief whammeler and Barry Foster his ancient, one-legged enemy. It was glorious.