You would think after all the nice things the newspapers have written about The Wire (note my almost perfunctory award, above, of five stars) that its creators, David Simon and Ed Burns, would give the press a free pass in their relentless examination of why Baltimore is such a basketcase of a city. But oh no, season five came back last night like a bitch on heat, scenting something rotten in the Fourth Estate. Its nose has been refined, of course, by its previous seasons where the police, longshoremen, politicians and teachers have all come up smelling of manure.

At the centre of the cesspool are the city's mean streets, run as alfresco drug markets by the pathetic, psychopathic potentates thrown up by Baltimore's black ghettos. The Wire's conceit is that the drug dealers' feuds and power struggles are the product of social decay and are replicated with disturbing similarity within every other decaying sector of Baltimore life, particularly its public institutions.

It took 23 minutes before we actually left The Wire's usual milieu and arrived at the Baltimore Sun, which is not only a real newspaper (any British drama would carefully rename it The Bugle) but the one where David Simon wrote for many years. By then we had been primed to suspect the printed word. A neat opening scene had a young gangster being set up by the cops' photocopying machine, which he had been persuaded to believe was a lie detector. His hand taped to its glass, the machine spewed out a piece of paper with the word “LIE” on it. The boy sang like a wounded canary. The episode was called The Bigger the Lie the More They Believe.

Yet beneath all the cynicism, you can detect the faint heartbeat of idealism, even old-fashioned American optimism, in The Wire and several times the episode acknowledged the righteous power of the press. The problem is the Sun is in almost as bad shape as the bankrupt police department, whose ranks haven't seen “an honest payroll” in weeks. Because of cut-backs, the paper no longer has a transport reporter, stories are missed, more lay-offs are coming and morale is low. In a lovely scene two reporters look out of the window with complete incuriosity as smoke rises from some conflagration.

You didn't have to be up on the accumulated backstory told in The Wire's previous 50 episodes to get plenty out of this opener to its final season. Even if you do not know the personal travails of Detective Jimmy McNulty, you could not have failed to enjoy the British actor Dominic West's lascivious drunk scene last night. Nor did you have to know that the political operative Norman Wilson (played with relish by Reg E. Cathey) was a former newspaper man on the Sun to enjoy the truthto-power tongue-lashing he gave the sleazy mayor.

And the dialogue, everywhere you can make it out - and the “black-speak” is not always easy - is a joy. A senior cop last night invoked the concept of professionalism to keep at bay his men's wage demands. “Professionals get paid,” it was pointed out to him. “That's why they call them[i.e. whores] pros.”

Much of the budgetary problem within the Baltimore police department is down to the mayor's commitment to education, education, education. But, if you saw any of series four, you will know money alone won't solve anything. Nor can underfunding explain the extraordinary fact that five million British adults cannot read or write properly. Can't Read, Can't Write was a typically half-baked attempt by television to do something about it. The format gave nine illiterates just six months (why?) to get reading and provided as their tutor the over-emotional, fuzzy-haired Phil Beadle, a musician turned teacher who admitted he has never taught anyone to read in his life, but is a bit of a TV star.

What we discovered in the first of three instalments is that illiteracy does not have a single cause. A grandmother called Teresa, who apparently could not read the word “ham”, had incredibly just never been taught. Now she has been and is already doing fine. But Linda, a cultured Shakespeare-quoter, married to a Guardian reader, just had a visual blank and made progress only when she physically made the shapes of letters.

Nothing, however, was getting through to James, the plumber. It surprised me that no one mentioned an IQ test or, indeed, dyslexia. This programme needed to be far more, well, educational. Undeniably, however, there is something very moving about hearing someone's first, vowel-mangling attempts to read a sentence. And Can't Read, Can't Write knows it.

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