Last Night's TV - Scenes from a Teenage Killing, E4; How TV Ruined Your Life, BBC2; Pleasure and Pain with Michael Mosley, BBC1

Morgan Matthews seems to be carving out a niche for himself as television's foremost monumental mason. His Bafta-winning film The Fallen, which catalogued every British armed forces death in Iraq and Afghanistan up to the point of its transmission, was a documentary cenotaph, three hours long and extraordinarily rich in its unfolding of bereavements that usually only occupy a few lines of newsprint. Now he's given us Scenes from a Teenage Killing, which recorded every violent teenage death in 2009. Like the earlier film, it merely highlighted some cases in passing while exploring others in much greater depth. Unlike the other film, it had a polemical edge to it, not over-obtrusive, but shaping the material Matthews had gathered.

His film had been crafted as an implicit rebuke to the standard media shorthand for teenage murder, which tends to posthumously enlist any victim – but particularly young black males – into a "gang" and enlist their deaths as yet more evidence for the broken state of society. There isn't any way in which you could present this as evidence for society's health, of course, but Matthews wanted to give space to the friends and relatives of the dead so that they could recover those they'd lost from this simplifying narrative. And he used the death of Shevon Wilson, a 17-year-old from Bristol, stabbed outside a local pub, as the central spine of his film, in part because it shared so many features with other teenage deaths.

The proud territoriality of grief was one element that ran throughout the film, the sense that mourners had a status as the bereaved that they would defend with some ferocity. Shevon's "shrine" – one of those melancholy cairns of flowers rotting in their cellophane – was originally opposite the pub outside which he'd been attacked, and had become a focus for tense face-offs between his friends and the beleaguered publican, falsely believed to have been related to the killer. Shevon's mates were indignant at the thought that they constituted a gang, rather than a group of friends ("people say it because they're mentally circumcised in their intellect," one of them said angrily) but were nonetheless fiercely proud of their solidarity. What does the exact word matter, you thought, if retaliation against the killer's relatives could be mooted as a desired response?

Violence pervaded this deeply melancholy film – a necessarily narrow window on a society in which young men always seemed to be just a few angry words away from bleeding their life out on a pavement. Violence followed violence, as in the case of a nurse who'd been forced to move home with her children because she'd given aid to a dying boy and had been prepared to testify in court about what she saw. The killer's friends threatened to rape her young son if she didn't keep quiet. And death didn't appear to chasten anyone. After the emotional funeral of one young boy in south London, the mourners emerged from the church to find that boys from the next postcode over had arrived to shout insults and threats. Outside the Old Bailey, the families of accused and murdered started fights in the street or muttered dark threats about violent retribution: "It's the East End way, innit," said a woman whose niece had been killed in an arson attack. "A life for a life... it says that in the Bible." Exhaustive connoisseurs of their own sorrow and hurt, far too many of those featured here appeared to have no ability to imagine that their antagonists might feel pain or fear as well. Matthews's film was a triumph of empathy in one regard – patient and thoughtful about what murder leaves behind it – but it also recorded a society in which empathy seemed to be a dying virtue.

It made for a slightly uncomfortable juxtaposition with the first episode of Charlie Brooker's series How TV Ruined Your Life, which advanced the proposition that television's preoccupation with disaster and death ("shouting boo in your mind," as he put it) had left us full of delusional fears about the world at large. It was something of a shotgun assault on the medium, ranging from doomy news priorities to public information films, and cutting from real archive clips to pastiches that were good enough to make you do a double-take. But it was very often funny too, particularly when reminding you of 999's appetite for the wilder fringes of human mishap. "Have you ever thought what it would be like to be stuck in the path of a runaway digger?" asked Michael Buerk gravely, with the implicit suggestion that if you hadn't you'd been living in a state of foolish denial about the looming threat of rogue excavators. There was also an excellent parody of a Horizon-style doomwatch programme – "If Pens Got Hot" – which used a global outbreak of ballpoint combustion to mock the Chicken Little aesthetics of such formats.

In theory, Pleasure and Pain with Michael Mosley is a popular science programme about the neurology of human sensation. In practice, it just seems to be an excuse to torment Michael Mosley. In the course of it, he did a piece to camera from inside a rotating Zorb ball filled with soapy water, took part in a chilli-eating contest, had his calves waxed, delivered a bit of script while immersing himself in freezing sea-water and – most impressively – while plummeting headfirst on a 220-metre bungee jump. The science was a bit of an anecdotal miscellany, frankly, but Mosley's resilience in the face of his producer's appetite for novel spectacle was genuinely impressive.