56 UP/THE UP SERIES The latest installment of this groundbreaking documentary series represents a bit of a holding pattern. The 13 British men and women who have been filmed at seven-year-intervals since they were 7 are now in the space between middle age and old age, and they want us to know they’re not dead yet. Essential viewing nonetheless. The release of the box set, which includes all eight films, allows viewers new to the seris to catch up. Extras: interview with director Michael Apted, subject biographies, photo gallery; filmmaker’s statement. (First Run Features, $29.95/$79.95) Full story for BostonGlobe.com subscribers.