The Hour (BBC2)

A return to a gossip-filled 1950s newsroom.

Yes, it could still go wrong: after all, Abi Morgan's series The Hour (Tuesdays, 9pm) is in six parts, which leaves plenty of room for soufflé-like deflation. But on the evidence of the first episode, I very much doubt that it will. This Bakelite and cigarette-smoke drama, set at the BBC at the moment when crusty newsreels were forsaken for news programmes as we know them now, with presenters and proper stories, really is cut from superior cloth.

Which is why, I suppose, people insist on comparing it to Mad Men, for all that the two are essentially so different (Lime Grove studios in the 1950s might be less flash than Madison Avenue in the 1960s but the former is, rather oddly, by far the more modern of the two in its attitude to women). Before I launch this praise-fest, though, we must note the one thing - it's quite a big thing - that is wrong with the series: the casting of Romola Garai as Bel Rowley, newly promoted producer of the BBC's happening nightly news show (also The Hour).

Thanks to the afternoons I've spent in the British Library of late, listening to recordings of professional women from the 1950s (I'm writing a book about a group of them), I can tell you for a fact that she sounds all wrong: too soft and insufficiently posh. She looks wrong, as well. The 1950s was a time before youth, a time when women, no matter how young, looked like their mothers.

Garai's distinctly dewy appearance - pale lipstick, unset hair, not much powder on her pretty nose - only serves to emphasise her exceptional position as a woman in charge of men, something her real-life counterpart (the character is inspired by the BBC producer Grace Wyndham Goldie) would have done everything in her power to minimise.

In one scene, she even forgot to bring her handbag with her as she exited a restaurant. No! In the 1950s, women clung to their handbags as if they were both lifebuoy and shield. A woman would no sooner forget to pick hers up than she would forget to put on her underwear.

In every other respect, though, The Hour is close to faultless; I would watch it for Julian Rhind-Tutt's spectacles alone (Rhind-Tutt plays Angus McCain, eyes and ears of the ailing prime minister, Anthony Eden; his glasses are as heavy and as dark as a black-leaded fireplace). Morgan's script, with its debutantes at one extreme of the social scale, and its, erm, rather flexible journalists at the other, perfectly captures a decade that was at once clenched and quietly revolutionary (and how delightful that in the month when the News of the World scandal went nuclear, The Hour showed a BBC journalist hand a copper a few banknotes, that he might be allowed access to the police mortuary).

What's more, Morgan has dished up a neat little mystery, too: why has the beautiful Ruth Elms killed herself and what is her relationship to an academic recently murdered in a Tube station? Yes, occasionally, the dialogue plods, 21st-century attitudes having unaccountably been allowed to seep in. "What is it about men?" asked Bel, as the men retired for their port. "You always need a tiny corner where we can't reach you." (I think she would have got her coat and left, silently.) But with a cast this good, you must be in full nit-picking mode for this to spoil things.

Ah, the cast. Journalists are always fun on screen. This is because journalists are such fun in real life. Gossipy and unclubbable, they make the best company. I love Dominic West as Hector Madden, the show's presenter, who has a smile so sly you seem to hear the rattle and ting of an old-fashioned cash register every time he flashes it.

Ditto Anna Chancellor as Lix, a boozing foreign correspondent. Best of all, though, is Ben Whishaw's Freddie Lyon, resident genius of The Hour. I used to have my doubts about Whishaw; his performance as Sebastian Flyte in the 2008 film version of Brideshead Revisited was unremittingly awful. But here, he is mesmerising: a sort of ferret-fox man, all instinct and nose. I hope very much that Freddie will get his scoop and that when he does, it will shake the establishment with geological force.

Rachel Cooke trained as a reporter on The Sunday Times. She is now a writer at The Observer. In the 2006 British Press Awards, she was named Interviewer of the Year.