The BBC Up documentaries—which have revisited a slowly dwindling group of people at seven-year intervals—imply that the value of the series outweighs any cost to the subjects, who were chosen when they were seven. We’re told with understood irony that a former participant who edits documentaries declined to be filmed for this installment, which includes participants and former participants commenting on the experience of being lifelong documentary subjects. Their largely negative or only superficially positive responses make me feel guilty about finding the series so fascinating—and should make the filmmakers feel even guiltier. The footage isn’t brilliantly edited, the subtext is often avoided or ignored—though this may be why the documentary doesn’t seem heavy-handed. Intending to study the degree to which social class would determine the subjects’ destinies, the series actually documents something more filmable—the degree to which the subjects believed social class would determine their destinies and the degree to which they believe it has. The idea that each participant is unfulfilled until he or she marries—implicit in the emphasis on the spouses and children of those who have them and the repeated questioning of those who don’t—eventually prompts one late bloomer to insist he isn’t gay. Another lonely heart, who’s made a conventionally appealing lifestyle change since the previous installment, is very nearly portrayed in the terms of a personal ad. Directed by Michael Apted (The World Is Not Enough). 139 min.