Two Decembers ago, Andrew Davies made Othello a Metropolitan Police commissioner. Now, in The Second Coming (9 and 10 February, ITV1) Russell T Davies has brought Christ back to modern-day Manchester as a video-shop assistant. You don't have to have "high concept" to get ITV interested in serious drama but it seems to help.
The younger Davies's concept has won a few headlines but is not in itself particularly clever. A thousand writers must have thought of bringing Christ back. Even I have harboured the idea (I wanted him all hellfire and unforgiving) and I'm not even a dramatist looking for work. What was special about The Second Coming was the execution: how Davies made the Christ figure's humanity interesting, his sure touch predicting how the masses and the mass media would react, and the theological sure-footedness that led to the piece's heretical denouement. This was not satire, nor was it fantasy. It felt scarily real.
To make it so, Davies had to convince us that Steve Baxter, the loser with three O-levels who had never been further than the chip shop, really was the Son of God. He did so economically. Holding his first congregation of internet "anoraks and nutters" in the Maine Road football stadium one evening, Baxter recalls the lyric "The future's so bright I've got to wear shades" and conjures broad daylight. In the age of rolling news, this miracle is so well attested that no one can really deny it.
In a believably pusillanimous response, the Prime Minister calls the event "a matter of individual faith" and, eventually, an emergency coalition of the world's churches "welcomes" Baxter as "the representative of the Lord, our God". The people on the whole, however, are up for it at once, and the media, which are not ridiculed in this piece, understand it, replaying repeatedly the moment when a woman reporter abandons professional detachment and begins to believe.
Once we accept that Baxter is the son of the New Testament God, we believe all kinds of other improbabilities, too. Evil becomes credible, even the kind that lights up characters' eyes eerily, the unimaginative trick chosen by the director, Adrian Shergold. There is much evil around - in malicious chief constables, ranting widows and pub bombers - but its most creepy incarnation is the lonely, overweight onanist Johnny Tyler (Mark Benton). In bed with a pile of soggy chips, he wriggles with glee as martial law is declared and judgement day approaches, the hour when everyone will be as damned as himself.
Baxter says the only way to ward off the evil hour is for mankind to write a third Gospel telling itself how to live. Soon hundreds of manuscripts are piling up in his headquarters but he has no time to read, let alone assess them. The deadline provides such narrative tension you dare not even think of missing part two. Is Davies up to writing his way out of the predicament? What would a new Gospel say?
Against the metaphysical challenge, however, is the problem, almost equally hard, that Davies set himself of getting us interested in Baxter. Here, he was helped by his leading man, Christopher Eccleston, who is one of the most irritating yet also compulsive actors on television. Having carried his chippiness with him all the way from Our Friends in the North, Eccleston even managed to make eating an act of class resistance. But the point is that Baxter is nothing special, not even especially likeable.
The blinding revelation that he is God comes outside a nightclub at the moment he realises his best friend, Judy, has been in love with him all along. We later learn that he is a virgin, and in some way the sexual revelation seems to be linked to the divine one. The link is not stressed, however, and unlike Scorsese's Christ, who was loin- tormented, Davies's is much more frustrated by intellectual inadequacy. He says he is trying to download 50 million mega-bytes of information on to a pocket calculator. He is a mixture of divine wisdom - refusing to perform miracles on demand - and contemporary frailty. For instance, he finds being a celebrity a turn-on.
His saviour is his disciple-lover Judy, played by Lesley Sharp, who surpasses even her performance of 2001 in Davies's Bob and Rose. Sceptical of his divinity, in love with him, tempted by the devil, she realises in the end that God's final loving act is to abolish Himself. Now that man has the ability to create life (by cloning) and destroy the world (with wars), he has become a god: it is time he began to behave like one. So the third Gospel is recorded by closed-circuit television cameras as Baxter knowingly eats her poison-laced pasta (this scene sounds bathetic; it is not; it is heartbreaking). This time there will be no resurrection.
Davies thus kills off God. Unlike that other atheist, Philip Pullman, who kills a senile God in His Dark Materials, however, there is nothing vainglorious in this patricide. Davies's final scenes show that the world minus the Almighty is a lonelier, bleaker, if more grown-up and (occasionally) more responsible, place.
My thought for the day is to pray that The Second Coming represents the second coming of serious, one-off drama to popular television. I have already, in this column, called Russell T Davies the most gifted television writer to emerge since Andrew Davies. The comparison I now lean towards is Dennis Potter.
Andrew Billen is a staff writer on the Times