The station is planning a version of the birth of Jesus in the fast- moving, rough-tongued style it has already used to bring comic-strip heroes to the airwaves. Traditionalists are shocked and outraged at its leaked contents.
Secrecy has surrounded the project, nicknamed "Judge Jesus" by those working on it. But a draft script obtained by the Independent on Sunday portrays the Virgin Mary as a moody character who calls Joseph, or "Joey", a "bastard" and says "Oh, shit." Confronted by a dazzling angel Gabriel, she blurts out "Oh my God!" The angel himself talks in the language of modern clubland. "Don't panic, guys," he tells the startled shepherds. "Check it out, okay?"
There are only two Wise Men - called Salman and Hussein - in this version of the Greatest Story Ever Told. A youthful audience of around half a million is expected to hear the five three-minute episodes, to be broadcast on Christmas Eve.
The episodes will be in the "audio animation" style first used by Radio 1 in April last year for an adaptation of Batman stories which were meant to boost its flagging ratings. Scenes will be short and punchy (never more than 45 seconds long, and always ending on a cliffhanger), with plenty of sound effects and dialogue laden with humorous one-liners.
"It should be like being in a cinema with your eyes shut," says the writer, Paul Powell. Along with the producer, Dirk Maggs, he was responsible for putting the cult comic hero Judge Dredd on radio earlier this year. Now the pair are aiming to smash audience preconceptions about the Nativity.
"We wanted to make the language more relevant to a Nineties Radio 1 audience," says Mr Powell, who took as his text the New International Version of the gospels of Matthew and Luke. A member of the Spitting Image script team and a comedian in his own right, he admits to being "a cynical Christian". He describes his version as "fast, frenetic action", with Mary as "a bit of a nag" and Joseph as "clueless".
Episodes will be recorded tomorrow and Tuesday, for broadcast during a three-hour edition of The Big Holy One, Radio 1's first religious series, which was launched three years ago and has won two Sony Awards. Past shows have included features such as "Heretic of the Week", "The Joy of Sects" and "The Actress and the Bishop". The show is produced by an independent company, Burning Pictures, and fronted by Radio 1 DJ Simon Mayo, who is also a believer.
"It is absolutely not blasphemous," he said. "Jesus is hardly in it. He just makes a few gurgling noises. We've extracted the St Michael out of everything else in the story, but the version that we all know and love and that gets put on the Christmas cards is total nonsense anyway - the Wise Men were never there with the shepherds for a start - so why shouldn't we mess around with it?"
But Margaret Brown, a leading member of the General Synod, the Church of England's ruling body, says it is "disgusting" and should not be allowed. "If they were doing this about Mohammed, the Muslims would shriek and rage about it."
Mrs Brown plans to bring a private member's bill to Synod in the new year calling for the Government to crack down on blasphemy, bad language, sex and violence in the media. "They are demeaning the Blessed Virgin Mary, mother of our Lord," she said of the series. She added that she could not believe that those behind it could be Christians.
"They're not going to get away with it," said Kieran Conry of the Catholic Media Office. "I wouldn't like to be on the BBC switchboard that day." He expects an outcry in advance. "In the light of recent reviews of what people expect from the BBC, they might find themselves battered into submission."
Simon Mayo has already been before the Broadcasting Standards Council this year. In July, his television show, Confessions, was ruled to have exceeded the bounds of taste and decency and encouraged anti-social behaviour. But he has no reservations about the Nativity. "Radio 1 audiences are familiar with having their superheroes portrayed in this way. The station has come up with a very acceptable, post-modern way of telling stories, and this is a story with raw material far more exciting than Judge Dredd."
Adrian Reith, a director of Burning Pictures, said the project was an attempt to "rescue a story that is too well-known and too familiar from the hands of Franco Zeffirelli and the school drama teacher". He said: "The Bible has been translated from Hebrew, Greek and Aramaic into all kinds of languages in the past. We thought it was time to translate it into Radio 1."
The series follows the traditional Nativity plot, starting with the Wise Men packing to follow the star, which one says will take them to Emmanuel. "Who on earth is she?" asks his partner. Told he is going to meet the King of the Jews, Salman says it is a waste of time. "If he is a member of royalty, he's probably out skiing." When Mary tells her husband she is going to have God's baby, he calls off their engagement, accusing her of being "blasphemous, offensive and downright loopy". "I'll be a laughing stock," he says. "I'm a descendant of King David, for God's sake." What he is, she says, is a bastard and a crap carpenter who can't even make a decent birdbath. "Mary mother of God!" she says in exasperation. "Oh no - that's me."
In Bethlehem, the keeper of the inn where they shelter has a wife who urinates in his beer. Shepherds in the fields are dreaming of a bloody revolution when they encounter the angel. One tries to explain it away as a freak ball of lightning, a collective hallucination or three sheep standing on top of each other. "Bollocks it was!" says another. "Let's get going."
When the child is born, Joseph thinks it's a girl. Whenever someone hears the baby will be called Jesus, they suck in their breath and say: "That's a bit controversial."
All the cows in the stable moo, except one mad bovine that quacks. The last episode, to be broadcast at 11.55pm, has the couple fleeing to Egypt.
"Everybody knows what happens in this story," says Simon Mayo. "Our task is to tell it so brilliantly, and make it so funny, that they don't believe it will end that way." A spokeswoman for Radio 1 emphasised the script was a draft. She added: "This is a Sony Award-winning show telling the story in a way that our young audience will understand."
RADIO 1 is following a well-worn path in presenting aspects of the life of Christ in a controversial way, writes Vanessa Thorpe.
In 1988, Martin Scorsese's The Last Temptation of Christ was withdrawn from Britain after protests. The film provoked demonstrations, was picketed at the Venice Film Festival and condemned by the Vatican. The offending scenes showed Christ on the cross imagining sexual intercourse with Mary Magdalene. Renewed protests followed the announcement that the BBC had bought the TV rights in 1991.
A decade earlier, Monty Python's Life of Brian provoked calls for prosecution. The film contains a spoof Nativity scene, an unconventional Sermon on the Mount, and, most controversial of all, a parody of the Crucifixion.
In 1969, Dennis Potter's play Son of Man, which portrays Christ as an angry man of the people, caused a furore when shown on TV. It was revived this October in an RSC production and met little religious complaint.
In March last year the European Commission on Human Rights agreed there was a prima facie case that British blasphemy law contravenesrights of freedom of speech. The case came before the commission when the British Board of Film Classification banned a video called Visions of Ecstasy, which interprets the ecstasy of St Teresa of Avila as a sexual fantasy about Christ.
The only successful use of the law in the past 75 years was Mary Whitehouse's private prosecution of the publishers of Gay News which printed a poem describing a homosexual fantasy about Christ.