Television: Supernanny fragilistic: the weak link in the Mary Poppins legend

A documentary on the complicated and colourful life of a quintessential English writer is probably the last place you’d expect to hear a story of a grim Irish adoption. But then nothing about PL Travers, the subject of The Secret Life of Mary Poppins (BBC Two, Saturday), was straightforward.

Travers wasn’t English at all; she was Australian, something she didn’t reveal to even her friends, and the story of how she came to adopt a baby in Killiney, in south Co Dublin, in 1940 was bizarre.

When Madge, her housemate and maybe lover, moved out after 10 years, Travers, then 40 and single, decided to adopt a child. “I thought that sort of thing only started to happen in 2005,” said its presenter – and Mary Poppins fan – Victoria Coren Mitchell.

When Travers, who moved in arty circles, heard that WB Yeats’s biographer Joseph Maunsel Hone had again been left holding the baby – this time twins by his son and daughter-in-law – she offered to adopt one. He suggested she take both, saying, “Take two: they’re only small.” She wanted only one, and, on the advice of her astrologer, she adopted Camillus.

Their relationship was troubled from the start, and although she created the byword for the ideal nanny, she had little interest in or patience with children. Camillus knew nothing about his adoption until a 17-year-old Irish boy arrived in London to tell him they were twins. This fascinating chapter, less well known than her fight with Walt Disney about his 1964 film of her book, which she hated, was only a small part of Travers's story.

Camillus is not mentioned in the film Saving Mr Banks, as, according to Coren Mitchell, it is "too messy for Hollywood, which craves order and redemption".

There's always a fear that a documentary – even a Culture Show special timed for broadcast with the launch of a Disney movie – is going to be a fluff piece, but Coren Mitchell is no gushing pushover. Although the programme was topped and tailed by scenes from the glitzy London premiere of the movie, which stars Emma Thompson as Travers, this was an entertaining but serious biographical overview of a writer who even a fan such as the engaging Coren Mitchell said "sounds like a nightmare, but it was brave of her to speak up for herself".

"Fluff", in London's Liberty department store, are the plebs or browsers who are unlikely to buy any of the high-priced fancy goods on offer and are therefore best ignored. Or so new staff were told during an instore training session shown in Liberty of London (Channel 4, Monday). Instead the new crew of immaculate girls and boys were given tips on "grooming" likely big spenders – a most unfortunate choice of word. Much as with the fascinating series about Claridge's hotel last year, a documentary crew was let in for a three-part observational series, but shops, no matter how high-end, just aren't very interesting. Even the second series of The Paradise, the BBC's Sunday-night drama set in a Victorian department store, is flagging – although at least they can make things up to keep the interest going.

At Liberty, once you got over gasping at the £1,995 stuffed bear, the five-pound bar of chocolate, the piled-high goods that the artist Grayson Perry in his court shoes and Liberty-print evening coat called “ethnicnacks” or the three men oohing and ahhing over women’s shoes (even if one of them was Manolo Blahnik), it all became rather dull and repetitive.

Claridge’s emerged looking aspirational and seriously posh. Liberty just looks silly and irrelevant. How they’re going to get two more episodes out of dull goings-on is a mystery I’m not interested enough to see solved.

That said, Liberty of London was a piece of hard-hitting investigative journalism compared to Men in Black (RTÉ One, Monday), which was little more than an hour-long PR gush for a security firm that supplies big events with bouncers. Once you've seen one shot of a bloke in a high-vis vest, the company name writ large on the back, checking tickets or keeping a crowd in line, there's not much need to see another. I suspect Allan Gannon, the owner of Frontline Security (is there only one security company? Couldn't others have been included?) has such long experience of controlling access to the more interesting areas of gigs that he deftly kept the film-makers back from anything that might have made for an insightful, never mind entertaining, documentary.

Few formats are as elastic as the quiz show. University Challenge, with Jeremy Paxman sighing and rolling his eyes – he's getting more theatrical each season – and The Cube, which makes no sense at all, are both quizzes, so anything goes. What tends to be common to all, though, is tension – something sorely lacking in Division (RTÉ One, Sunday) a new quiz show that's like one of those office team-building events that everyone except the HR department hates.

With 32 contestants at the start, it’s notionally team-based – though we never get a sense of who the changing teams are as they are shuffled on and off until their numbers are whittled down to two.

The studio is flooded with ultrabright light, and the quizmaster, the former newsreader Anne Doyle, stands behind an industrial-looking cauldron while the contestants are kept in two ugly metal sheds. It's like a nightmarish dream sequence in a news item about ghost estates. The contestants have the exhausted look of people filmed for longer than they imagined possible as the camera tries to capture a few funny or entertaining asides.

There were a few, such as a young woman who didn't know what a taoiseach is or the young man who, when someone mentioned Charles Haughey, said, "Oh, yeah, I remember. We did him in history."

A few tweaks – harder questions for a start, and it's tediously long and drawn out, with just four rounds of questions in nearly an hour – and Division could be an enjoyable enough afternoon quiz. In its present format, it's not smart enough for a prime-time slot.

tvreview@irishtimes.com