The Weekend's Viewing: In Russell Lewis, Endeavour has a writer who knows when to stop

Endeavour, Sun, ITV1 // The Genius of Marie Curie – the Woman Who Lit Up the World, Fri, BBC2

Your affection for a television programme can sometimes boil down to the smallest things. I've fallen for Endeavour over the last four weeks, a classy bit of Sunday-night escapism that, on paper, had some prejudices to overcome. It's a spin-off for one thing, which always feels a little indolent as a commission. It's also two hours long, which needn't be a defect in a drama, but does put quite a high premium on it having some compensatory virtues. And it's a period piece, which raises the danger that a Bakelite telephone or a vintage Vauxhall Cresta will used as a substitute for the kind of qualities you can't simply hire from a prop house. But Endeavour has risen above all these disadvantages, largely because in Russell Lewis's hands it knows when to stop.

Take Proverbs 26:11 as an illustrative text. The biblical text came up when Morse was called back north by his sister to visit his ailing father, an undemonstrative log of a man who chided him for making a fuss. “Proverbs 26:11,” she explained, was what Morse's father had muttered when he learned that his son had returned to Oxford as a policeman. And the attractive thing about that scene was that she didn't explain it further to Endeavour and the drama didn't explain it further to us. There was a kind of clue, to bridge the gap for those who didn't know. Morse implicitly paraphrased it as “returning to the scene of the crime”. But to get that it was the verse about a fool returning to his folly “as a dog returneth to his vomit”, you either had to know, or go and look it up.

The restraint made that moment far more believable than it might otherwise have been, the kind of modest opacity that real life is full, of but television dramas often like to tidy out of the way, for fear that an audience will take umbrage at being presented with anything less than utter transparency. And it feels there's an analogy in that withholding for the careful underplaying of Shaun Evans as the young Morse. The visit home to his father rounded out the character a little more; that taciturnity is inherited, you suddenly see, and Morse's relationship with Roger Allam's bluffly paternal DI takes on a new aspect. But everything is done with virtually nothing on show. In a very touching moment at the end of last night's episode, Evans conveyed Morse's confused emotions at the death of his father with nothing more than a stricken fussing with his hands, gestures half completed and then cancelled. That was worth 20 minutes of gun-play.

The Genius of Marie Curie – the Woman Who Lit Up the World, the latest of BBC2's Friday-night profiles of great scientists and artists, promised “one of the greatest sagas in the history of science” and didn't entirely disappoint. Hardly surprising, really, that her story has so often been filmed since it has everything – romantic passion, intellectual determination, war scenes and two Nobel prizes in two different scientific disciplines. It did seem a little paradoxical, though, to begin with the scandal of her relationship with Paul Langevin, an affair that led the anti-Semitic newspaper L'Action Française to inveigh against “this foreign women” and whip up a mob that beseiged her house. “A woman's sexuality and her science were somehow seen as one and the same,” explained one of her biographers, implicitly drawing a contrast between those benighted times and ours.

So what, one wonders, would Marie Curie herself have made of the fact that what was intended as a tribute to intellectual genius began with an examination of her private life? Would she have taken it as indicative of a general tendency to sex up the stories we tell ourselves? Or might she have asked herself whether a similar exercise about Einstein would have begun in the lab and not the bedroom?

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