I think it was Cyril Connolly who once said of George Orwell that he couldn’t blow his nose without moralising on conditions in the handkerchief industry. That might equally apply to Ken Loach. I can’t imagine what he must be like to go on holiday with, or accompany to a supermarket or restaurant. For our Ken, all of life is a series of precariously balanced injustices and exploitations, a lot of rocks waiting to be turned over. He doesn’t have a single crusade: his righteous anger is panoramic and retrospective.

It is easy to roll your eyes and dismissively mock Loach. He so studiedly doesn’t fit any of the modern celebrity models of film-maker or television-purveyor. He is a greenroom lawyer, a one-man awkward squad, the chap who coughs when you would giggle. He’s more like a director from the theatre than cinema, a Brechtian film-maker. Actually, he’s more like George Bernard Shaw. He shares all the Shavian strengths and weaknesses. There’s the propensity to pomposity and the bore’s need to tell you everything. He uses character as a cypher for ideology and a repository of polemic. His strength is the moral imperative, a social fury and the ability to construct compelling and moving stories out of subjects that are worth being compelled and moved by. Loach is a good thing. He is on the side of the angels, which is more than you can say for most Tristrams. If he weren’t here, we’d miss him.

It’s a Free World (Monday, C4) is his first work specifically for television since The Navigators. The heavily ironic title refers to the plight of desperate migrant workers who come to the free world and are free to take or leave the exploitation that’s offered to them. They are lied to and abused by gang bosses, cheated in sweatshops, hounded and deported by authority. It’s a classic Loach subject, treated in a predictable Loachish way. The actors are unknown, but produce award-winning performances. The dialogue is extemporised; the atmosphere and look are realistic, without ever slipping into the kitsch of docudrama. There is nothing to make it easy for the audience. This wasn’t black and white, it wasn’t about evil gangmasters and sacrificial-world workers. It was morally muddy and messy. Everyone has their troubles and justifications. As ever, Loach points the finger of blame at the system as perpetrator. Consumers and capitalism commit the big crime. The exploiters and exploited are just part of the inhuman machine for which we must all take responsibility.

As a drama, this was good in parts. The trouble was, the parts were separated by long passages of dull, repetitive exposition. It desperately needed a rigorous apolitical edit and an injection of human interest. As ever, you have the feeling that Loach cares deeply about humanity, but would rather keep his distance from humans. There’s a forensic inquiry, but a strange lack of empathy.

Secret Diary of a Call Girl (Thursday, ITV2) is as far away from the Ken Loach school of political drama as you could hope to get: the adaptation or, more accurately, exploitation of a titillating chick-lit memoir manqué about high-end prostitution. It is a measure of the unpredictable and unfathomable eddies of political correctness that circulate around television that, 20 years ago, it would have been impossible, unthinkable, to make a drama promoting prostitution as an aspirational career option for bright young women. But feminism has been suffocated and mocked to oblivion by the overt sexuality of celebrity and popular drama. Pornography is now seen as a postfeminist equal opportunity, so is widely used as a winning career move for girls.

This story of a happy hooker must have been chosen specifically as a vehicle for Billie Piper, the small-screen Scarlett Johansson, a girl whose pulchritudinous charm is greater than the sum of her assets. Her erotic relationship with television never ceases to surprise: from Doctor Who’s right hand to hand relief, kiddies’ favourite to dads’ favourite.

I can’t get terribly censorious about this Footballers’ Wives-style drama concerning the ins and outs of a vocational brass. But if I were a young woman, I’d find it pretty shabby and exploitative. You can either get angry at the moral abdication of so much hard-fought territory by TV executives, or you can laugh ironically at the silliness of their pretty little heads. Actually, I doubt that a feminist point of view ever crossed the producers’ minds. What they were thinking of was how to get Piper’s kit off, on the assumption that this was what most of the audience was thinking of. Whatever low expectation this production set itself, it quickly abandoned for some soft-focus, pastel porn that reminded me of Robin Askwith and the Confessions series, which passed for English eroticism in the 1970s.

Sex on television is a difficult gavotte of strategic elbows and knees and bumps-a-daisy. You spend most of your time as a viewer trying to peek round corners and under sheets. This was particularly unerotic and passionless, a bit like picking through a bedroom-furniture catalogue. Maybe the series will get interested in more than Billie’s bum later in the run, but my guess is that it will end up with the most pernicious of all female-demeaning clichés – the whore redeemed or punished by the love of a good man. As for Piper, her performance both in fake sex and as a fake sex worker lacked commitment, credibility and understanding.

You wait all season for a homemade TV drama with a contemporary theme, then three come along at once. Stuart – A Life Backwards (Sunday, BBC2) was another book adaptation that looked at homeless-ness, based on the true story of an unlikely friendship between a self-destructive, alcoholic, homeless outsider and a Cambridge writer who decides to transcribe his friend’s biography, for no better reason than that nobody has written the life story of a tramp before. Stuart suggests he tells it backwards, like a detective story, to make it interesting, and so the reasons for this sad, dysfunctional life unfold in reverse.

The friendship of this odd Boswell and Johnson, and the hanging presence of a tragedy waiting to work itself to an inescapable denouement, made it touching and harrowing and sad. The central performances, by Benedict Cumberbatch and Tom Hardy, were utterly believable, perfectly judged and balanced against each other. Although the plight of the homeless, abused and sick was the impetus for this story, unlike in the Loach version, the political finger-wagging and lecturing here were implied, not explicit; they became the background to a story of friendship and Stuart’s pitiful life. By putting the characters first, this ultimately made the moral far more affecting and memorable.

Neither It’s a Free World nor Stuart – A Life Backwards offered answers to the problems they raised. Only A Secret Diary seemed to imply that the solution to the world’s oldest profession was to make it like a brand-new postmodern profession. Then you can both join them and beat them.

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