Aberfan: The Green Hollow, BBC Four

Television is not a medium we much associate with any sense of the "sacred". It grapples with "momentous" frequently enough, in snatches of news tragically reported; it rings in, and out, the history that defines our lives. We may debate, equally, whether the small screen is replacing the big one as the bringer of what was once considered cinema art.

But for that far most elusive thing, the miraculously elevated experience shared across a nation, and somehow revalidated by that breadth of audience – rarely, so rarely.

But I cannot think of any better term than sacred to describe the 60 quietly shattering minutes of viewing that were Aberfan: The Green Hollow. BBC One Wales broadcast this film first on Friday, the 50th anniversary of the disaster, and no doubt it was right that the initial airing of this masterpiece should have been on the home territory of its tragedy. But it could have – should have – featured far higher in the national broadcaster’s pecking order than BBC Four.

Fifty years on, Owen Sheers has offered the tribute due from a poet laureate

No matter. Aberfan: The Green Hollow is the kind of film for which the international television industry invented awards. It will be a contender in so many categories that it’s hard to know where to begin, but writer Owen Sheers is surely the first candidate. Sheers has described it as “a film poem in the voice of Aberfan, both then and now”, and a better description for his verse drama could not be devised. Divided into three sections, “Children”, “Rescuers” and “Survivors”, it was certainly inventive in crossing boundaries – the one between the events of that terrible day in 1966, its immediate follow-up, and the present; and also that between the real-life protagonists (the survivors, that is) and the cast who represented them in the film.

Welsh acting talent surely cannot have more bounteous a spread to offer than was on display here: led by Michael Sheen, Siân Phillips and Jonathan Pryce, its magic stretched down to every single, very last participant, and democracy was the keyword, all those gifts being used selflessly, with no competition for billing. Real-life overlapped with thespian talent throughout: in the second, “Rescuers” section director Pip Broughton demolished the fourth wall, and we saw some of those who became in actuality involved in the tragic events effectively watching their experiences being recreated in a studio. Against the odds – and a first-off sensation that it looked a bit like an advert for a new German car – it worked triumphantly.

“How to talk about it?” was the film’s crucial question, coming shortly after opening footage showing dear, challenged Cliff Michelmore, for 24 Hours on that fatefeul evening of October 21 1966, struggling to. Sheers has written movingly of his apprehensions about approaching those directly connected to Aberfan – yet again, with new demands, the painful imperative of remembrance more acute than ever in this 50th anniversary year – but the result of their collaboration spoke with a truth that went beyond language. Its secret is best left to those involved directly in the process, but if you were looking for testimony it was there, visually, in the incredible contours of Siân Phillips’s haunting features (pictured, below left), every bit as much as it was in the tenderest details of family life lived in a particular place and time (pictured above). For the verse drama quality, Dylan Thomas’s Under Milk Wood (which was director Broughton’s last film) inevitably came to mind, but for cinematic power of the remembrance of childhood – and its tenderness – this went right back to the earliest, best of that cinema master, Terence Davies, no less.

Which are the highest plaudits, and this film’s manifold achievements went well beyond Sheers’s script, in the development of which Broughton must surely have played a significant part. The director’s sensitivity throughout struck home, more than supported by simply beautiful cinematography from Steve Lawes, and a magical score by Laurence Love Greed that knew as well when to keep silent as when to speak, whether its melodies came from Schubert or the juke-box melodies of the era.

All that said, the softly spoken glory here was Sheers’s language, his largely unrhymed verse, tetrameters, pentameters and variations thereon, the loosest of poetry flowing in line with speech rhythms, often (especially with Sheen) so close to prose as to be almost indistinguishable. Sheers's last verse drama offering was Pink Mist, which was about the experience of British soldiers in Afghanistan – again, seen through the prism of what went before, and what came after. Aberfan: The Green Hollow has gone many a mile beyond.

The overall kudos due is huge. Aberfan seems to have been left unmarked by any British poet laureate: 1966 was a year before the death of the ailing John Masefield. Three years later, Philip Larkin wrote a poem, “The Explosion”, inspired by an imagined disaster in the mines, but it's hard to escape a sense that the immediate memory of Aberfan is in there, too: the awful irony of that disaster was that the roll-calls for the missing were being called not for miners, but for their children. Fifty years on, Owen Sheers has finally offered the tribute due from a laureate, a post which, on this evidence, he may well one day occupy.

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