"56 Up" (PBS, Monday). Michael Apted's great, growing lifelong documentary project reaches late middle age. The series began (with a different director) in 1964 -- this franchise is more than twice as old as "Toy Story" -- to provide a "glimpse of Britain's future" as nascently embodied by 14 7-year-olds from different economic and cultural backgrounds; in its premise was the suggestion that the future had already been largely written. But the subsequent films (all directed by Apted and made for television, though sometimes released theatrically here), which return to the same subjects after seven-year intervals, argue that life is not that predictable, apart from the fact that we all get older (if at seemingly different rates of decay), if we live. They have become something bigger, grander, more universal. What we find in this latest episode, despite ups and downs, divorces and deaths and disease, is a great deal of contentment, and, barring contentment, acceptance, and barring acceptance, understanding -- the recompense age gives for taking away all that beautiful youth. (Each new film incorporates material from its predecessors, and so we see the characters at several ages, the young and the old and the in-between compounded into one.) And the story has grown over the years, like stories do, as spouses and children and grandchildren have come into the picture and grown old or grown up -- the series contains its own echoes, like a human canon. And more and more "Up" itself has become its own subject, not only its effect on the lives of its participants, but where the participants feel it has wrongly or insufficiently represented them. (Some have gone and come over the years; all but one is present here.) Still, as one subject says, "It isn't the picture, really, of the essence of Nick or Suzy -- it's a picture of everyone. It's how a person, any person, how they change.... It's not an absolutely accurate picture of me but it's a picture of somebody and that's the value of it." In other words, a picture of you.