Every seven years, like the passing overhead of a sociologically informative comet, the latest installment of filmmaker Michael Apted’s Up series hits theatres. In so doing, the newest multiple-of seven chapter in the saga, 56 Up, doesn’t just provide an update about the lives of a handful of average British citizens with whom we’ve developed an increasing (and in some cases uncomfortable) familiarity. We are also reminded about the project in its entirety, one of the boldest experiments in documentary cinema every attempted. Like few other nonfiction films – Shoah and The Sorrow and the Pity come to mind, along with certain Frederick Wiseman efforts – the Ups are a kind of institution, a piece of material history.

Unlike those other works, however, Apted’s series is characterized by an overall optimism. This could have to do with the project’s origins in television (56 Up, like every installment, was originally aired as a special on Britain’s ITV network), but more likely it speaks to the nature of the study. In 1956, Apted and co-producer Paul Almond interviewed a group of fourteen 7-year-olds from different economic and geographical backgrounds (upper / lower class; urban / rural; private / public school) and revisited the interviewees every seven years. The project, as each and every installment reminds us, was ostensibly based on a Jesuit proverb attributed to Francis Xavier: “Give me the child until he is seven, and I will give you the man.” But apart from this dubious nature vs. nurture assertion, in watching the series (especially the installments through 28 or 35) that Apted had a different suspicion which he scarcely conceal: that class origins in the U.K. were an almost ironclad predictor of destiny.

By the time we reach 56 Up, on the other hand, not only have many of the largest questions regarding the subjects’ lives (education, career, coupling) been largely settled. In many cases, those who have continued participating in the project, which includes all but one of the original 14 children, have become friends of Apted, or at least longtime sparring partners. If the Up series is, at its base, an indispensible document because its longitudinal study of 13 British lives is unprecedented in cinematic (or sociological) history, its latter-day stages are revealing of the slippage between discrete subject / interviewee roles and a kind of deep comfort within a knowledge-system, such that Apted, who we never see and seldom hear, becomes a “subject” nevertheless.

But then, the Up series has also borne witness to the tide of reality TV, a medium which treats “ordinary people” quite differently but subjectivizes them nonetheless. 56 Up is glossier, chattier, has a slicker and less obviously argumentative editing rhetoric. The sharp, precise BBC journalism of the earlier segments has given way to the soft focus and warm beige couches of Barbara Walters and Oprah Winfrey. This TV language, however, could well be Apted’s Trojan horse. Interviewees like Jackie, Lynn and Sue, the long-time working class threesome, are able to land pointed jabs at David Cameron’s federal cutbacks and Tony Blair’s pro-business New Labour policies, while still coming off as chatty and affable.

Apted has asked us to follow these lives for decades, on the assumption (quite correct) that everyone, however ordinary, has a story to tell, and that their very typicality will allow their lives to display larger social and historical shifts which, from the inside, are often “felt” but not entirely understood. But as Apted has grown more comfortable with both his subjects and with the language of commercial television, something else has happened. He is fixating much more of individual dramas and crises, as well as becoming besotted with “personalities.” This has been increasingly the case since 28 and 35, when Apted discovered that Neil, the homeless, manic-depressive intellectual, made for compelling TV.

But as we see in 56 Up, now that Neil has a more stable life, he is not quite as interesting to Apted. Instead, the latest film (and by extension, the State of Britain) is summed up by talkative, happy-go-lucky East End cabbie Tony. His class mobility, which would have been unthinkable under the premises with which Apted began the Up series, now virtually defines it. Perhaps there’s another scrappy, smiling “Tony,” someone we never see but whose effects are felt everywhere in 56 Up. And it seems that he has driven Michael Apted decisively to the center-left.