"Try to slow down your swing a bit, don't be in such a hurry, and keep your eye on the ball". Mr Morris, of the celebrated motors, is giving Oswald Mosley some golfing advice, but even semi-comatose viewers might spot that there is more than one application for these words. Mosley smacks the ball towards the green. "Not bad," says Mr Morris approvingly, "try aiming a bit more to the right, though." Lines of such clunking portent are an occupational hazard for viewers of biopics, because writers can rarely resist the temptation to compress the messy contingencies of a life into neat, thematic packages. And how you respond to Marks and Gran's series rather depends on how seriously you take such exchanges. Are the writers really in earnest, or are they having some fun with the form? The answer with Mosley (C4) is both, I think, and it is one reason why it oscillates so oddly between the compelling and the faintly ludicrous.

There are clearly moments when the giggles are intentional. In Episode Two, for example, there was the scene when the camera panned out from two martini glasses, lurching and slopping on a tabletop, agitated by the brisk coitus of Tom and one of his mistresses. "Marvellous timing darling," she says breathlessly, as they readjust their clothing, "the table's booked for 8.30." Sometimes, too, the jokes capture the contradictions of Mosley's career with a witty concision - "All my staff are members of the appropriate trades unions," Mosley assures a gathering of Labour faithful at his country house. "Even Cox there," he adds. "Mind you, I had to threaten him with the sack to get him to join." Jonathan Cake is good at the raffish insouciance needed to carry off such scenes - the depiction of the politician as a lounge lizard with dreams of glory. But he is less successful in depicting the darker side of Mosley - turning sulphurously caddish whenever destiny sounds its horn (like a vintage motorcar announcing its arrival on screen). When the long-suffering Cynthia asks where their party will be if no crisis comes along, he responds with the silky menace of a B-movie villain - "Oh believe me... the crisis is almost upon us". I think he even arched an eyebrow during the intimidating pause. It's only fair to add that the script doesn't give him much foundation for a more elaborate construction. There was a fine scene in which Mosley took Bob Boothby through a position paper he had written for Cynthia on marital fidelity, where you could see that this was a man who had press- ganged logic to serve his desires. But the shift from Labour firebrand to embryo fascist has been less convincing. One moment the croquet lawn is full of shirt-sleeved sons of toil, the next it is being used as a drill square for the New Party's honour guard; one moment Mosley is making passionate speeches about socialism, the next he is spitting venom at the Communists.

We know why his career has been forced to seek another course but we aren't offered many clues as to why it should have spilled in this particular direction, what innate cracks of character have failed under the pressure of dammed-up ambition. What's more the very late arrival of xenophobia (there has still not been even a breath of anti-semitism) is beginning to look decidedly protective on the part of the writers. That said it is still refreshing to see a drama on screen which is not about policemen, doctors or vets, and which, if it fails, does so because of ambition, rather than for lack of it.

Real Women (BBC1) - a title almost as presumptuous as The Truth About Women - arrives with the big push of a Radio Times cover and a very strong cast. It is an ensemble drama about a group of old school friends who have remained close despite the very different paths their lives have taken. Each one rather neatly represents a Problem Page dilemma - my husband is always belittling me, I daren't tell my friends I'm a lesbian, I can't seem to get pregnant, I can't meet Mr Right - and the script for last night's episode, in which the women went on a hen night, involved much raucous innuendo. They don't seem very real to me, but this one may get better.