Last night's viewing - Walking with Dogs: a Wonderland Special, BBC2; Paul O'Grady: for the Love of Dogs, ITV1

"My view is dogs are people too," said Marianne, at the beginning of Vanessa Engle's Wonderland film about the dog-walkers of Hampstead Heath. My view, in the interests of full disclosure, is that they're not. So I approached Walking with Dogs with a certain wariness.

When someone is asked what their dog means to them – as several contributors were here – and they reply, "The whole world", I do not, to put it mildly, identify a kindred spirit. I should have been reassured by the director's name. Because although Engle's film began with an ominous display of doggy sentiment, it was very soon clear that it was people she was interested in and not their frankly interchangeable companions.

Real dog-lovers would yelp at such a suggestion, naturally – the unique and irreplaceable nature of their pet being a fixed element in their world view. But the truth is that most dogs are interested in pretty much the same things and it takes a very doggy person to sustain a conversation about them for longer than three minutes. Fortunately, Engle had spotted that the dogs might be a means to an end, a way to get into conversation with strangers and find out about their lives. She opened, in fact, with a kind of nudging hint about her enterprise here, featuring a dog-owning vicar who found that his black lab was a useful opening gambit for perambulatory pastoral work.

The theme that slowly emerged was of the dog as unwitting social worker, a four-legged crutch that had helped an extraordinary range of people get through difficult times in their lives. There was a certain amount of eccentrity first. Marianne, say, whose infatuation with "little white fluffy animals" had led her to design a range of Swaroski-encrusted dog accessories. Or the businessman who walks the heath with five bichon frisees, followed at a respectful distance by a Filipino servant to pick up the dogs' leavings. But the heart of Engle's film were those for whom the dog was considerably more than a pet. Warren, for example, whose lethal-looking French mastiff, Frankie, was notionally a steadying influence. Warren had spent three years in prison for GBH, but was touchingly abashed about the details and insistent that Frankie was a step up to responsibility.

You might reasonably harbour some doubt about Frankie's ability to keep Warren on the straight and narrow rather than bodily tug him off it. But there were more reliable case histories. That of Zen, say, a boisterous pit bull who'd been picked up by his current owner, Martin, outside a dentist's 18 months earlier. Martin was a recovering alcoholic and his current bout of recovery, not coincidentally according to him, had lasted 18 months. Or there was Gilly, a woman who'd fallen on hard times after her partner walked out. Gilly wasn't managing to stay on the wagon quite as successfully as Martin. She'd been yellow carded by the homeless hostel where she lived for arranging an all-night party. But without the unjudgemental dependency of her weimaraner, Bluebell, you guessed that she might not still be there at all.

All the cutesiness that Engle managed to avoid appeared to have been siphoned off and injected under pressure into Paul O'Grady: for the Love of Dogs, a sickly combination of anthropomorphism (Ah! look... Paul's doggies are watching him on telly!) and animal hospital tear-jerking. In the final episode of the series (there have been no less than seven of these insults to the brain), O'Grady waved farewell to Battersea Dogs Home and took with him one of the Jack Russell-chihauhau-cross puppies that had done most of the heavy lifting when it came to making the audience croon. He also found a home for Rizzler the deaf samoyed. I'm glad Rizzler ended up in a loving home, but the programme itself needed to be bagged in plastic and disposed of in a responsible manner.