Last Night's Viewing: Eternal Law, ITV1Meet Britain's Chinese Tiger Mums: a Wonderland Film, BBC2

Sorry. Forgot to tell you about the bumpy landing," said Zak, at the beginning of Eternal Law, Ashley Pharoah and Matthew Graham's otherworldly new drama, after he and a rookie colleague had plummeted to Earth in a Yorkshire cornfield. Tom, the new boy, had gone all Fotherington-Thomas for a spell, gazing fondly at the stars and stroking corn stalks and frogs. "This is beautiful! This isn't a world in trouble, it can't be," he said. Which is one of the things that screen angels are supposed to do, after all – to remind us that heaven can be found on Earth if we only know how to look properly. It's what Clarence did in It's a Wonderful Life, and what countless other cinematic angels have done since.

Eternal Law proposes a cosmology in which angels operate as celestial social workers, deployed by a Mr Mountjoy (not God, I think, since he's described at one point as having wings) and given human form as a familiar Hollywood narrative cliché; in this case, the unwilling partnership of a bruised veteran and an idealistic novice. They could have been policemen or private detectives or even doctors, but as it happens they're barristers, mysteriously inserting themselves into York's court system to take on hopeless cases. They don't seem to have a chambers as such, or a clerk to get them jobs, but they do have a sexy landlady type, Mrs Sheringham, and an antagonist with a whiff of sulphur about him, a prosecuting lawyer played by Tobias Menzies.

Zak also has relationship complications – the other reliable duty of cinematic angels being to go all mopy over a human being and be obliged to choose between lurve and duty (think of Wings of Desire and City of Angels). The rules are absolutely clear: "Don't get emotionally involved with them, don't sleep with them, don't kill them." But sometime in the past, Zak has broken this rule with Hannah. The fact that he did in it a different body means that he recognises her but she hasn't a clue why he gets all stricken and stand-offish whenever they meet. At the same time, his temper is being tested by Tom's innocence, a quality that also raises a question or two in a viewer's mind. If Tom is so clueless that he tries to eat a banana without peeling it, how exactly is he going to cope with the intricacies of English case law?

The angels' first case was bonekickingly ludicrous – the trial of a man charged with a sniper attack on a street market. Tom naively took against him, while Zak, more experienced in worldly ambiguities, saw him as a soul in trouble. He also bent the celestial rules again by tampering with one of the witnesses, sidling up behind her on the bus and inducing a vision of the happy future that would follow if she was entirely candid in her testimony. Unfortunately, the only possible source of interest in such a fantasy – the friction between real-world justice and a heavenly one – is lubricated out of existence by the desultory nature of the plotting, which dispenses with consequences whenever they are awkward in favour of bantering jocularity and wing-flapping melodrama. The better angels of my nature have persuaded me not to go into detail about the embarrassing mismatch between the intensity of Sam West's acting and the triviality of the drama he's serving.

Meet Britain's Chinese Tiger Mums: a Wonderland Film – a study of the classic human disconnect (not just Chinese) between what you want for yourself as a child and what you want for your children as a parent – would have been better at 40 minutes and near perfect at 30. Unfortunately, like too many films these days, it was an hour long, which meant that it had to repeat itself just to fill out the slot. There were some lovely moments, though, and a terrifying glimpse of just how competitive the new school term can be.