The Weekends TV: Hilary Mantel: a Culture Show Special, Sat BBC2 / A South American Journey with Jonathan Dimbleby, Sun BBC2 / World's Most Dangerous Roads/ Sun BBC2

Not all writers talk as well as they write. In some cases, in fact, that's why they write, because the page is the only place they can be sure of staying in control.

But on the evidence of Hilary Mantel: a Culture Show Special, the author of Wolf Hall isn't one of them. I don't know whether a lot of her interview ended up on the cutting-room floor, but everything she said on air was worth listening to and a startling amount of it worth writing down so that you could savour its dry elegance of tone at leisure. She is a strikingly odd presence on screen – the voice a little tremulous at times and little-girlish. But she is also a strikingly smart one, capable of saying gravely serious things in a way that never excludes the dark comedy of life. James Runcie's film about her – unfussy and direct – followed the advice she herself claimed that she gives to aspiring writers. "Trust your reader. Stop spoon-feeding your reader. Give your reader credit for being as smart as you at least."

That advice for writers went on. "Concentrate on sharpening your memory and peeling your sensibility," she added. The interview she gave suggested that in her case life had done some of the peeling for her. Her attentiveness as an author, she said, had been developed very early, after her mother took a lover into the family home (her father retiring, with remarkable meekness, to the spare room). Aware that something was up but not exactly what, the young Hilary was always on the alert for clues and signals. "You really should know, for your own preservation, whether the devil is behind that door." The devil, incidentally, made his presence known to her in the family garden, in a sudden apprehension of evil that has left her permanently open to the idea of other realities.

Chronic illness did more peeling for her, resulting in weight gain ("I became the blossoming sofa-like creature you see before you") and infertility, a painful deprivation that she explicitly connects to her literary productivity. "What's to be done with the lost, the dead, but write them into being?" she asked wistfully. Talking of her wonderfully sly novel Beyond Black, she suggested that "if I hadn't had an education... if I hadn't learnt to put the brakes on [I might have been a medium]. You talk to the dead one way or another and you make it pay." Runcie backed her eloquence with a sequence of quiet, still images that didn't compete with the talking but offered a visual match for her sharp-eyed prose.

BBC2 spent most of yesterday evening in South America, starting with another of Jonathan Dimbleby's good news tours, in which he explicitly sets out to replace gloomy received opinions about developing-world countries with success stories. A South American Journey with Jonathan Dimbleby began in Bolivia, where the good news story was a bad news one with a silver lining – the fact that the country's many child workers have now formed their own union. He also found himself roped into a local wrestling match, getting properly enraged about the war on drugs on a small coca plantation and attending a concert of Bolivian baroque music in the heart of the rainforest, the cultural legacy of Jesuit missionaries.

World's Most Dangerous Roads was less concertedly high-minded, but the last of this engaging series did at least take you well off the established tourist routes, as Ben Fogle and Hugh Dennis drove over the Andes to the geographical centre of Peru, along roads that would leave a mountain goat sweating. They've pioneered a new kind of camera angle for this show, which you might call the passenger's side precipice view and this week the shots were terrifying enough to have you doing that mad flinching thing you do when you nearly clip someone's wing mirror and think you can shrink your car by sucking in.

Last week, I suggested that Appropriate Adult had acted inappropriately in concluding with photographs of the Wests' victims. I've learned since that virtually all of the relatives approved of this commemorative gesture. The women themselves might not have had a choice, as I wrote last week, but people far more entitled to speak for them than me did, and they said yes.