What do B&W loops from the early 20th century, recreations of color arcade loops, filmed striptease acts and interviews with early porn performers have in common?  Together, they form one of the first and most famous porn documentaries, put together in 1970 by top director Alex deRenzy... and frequently copied thereafter.  A narrator takes the viewer through the background of some of these early "classics" as well as the more modern material -- '40s to '60s -- some only a minute or so in length; others fairly long.  Included are a couple of famous works -- "Smart Aleck" with stripper Candy Barr, and "The Nun's Story" -- as well as deRenzy's own short, "The Masseuse" (thank goodness he got a lot better!), but overall, this will be watched more for its historic and informational value than whatever minimal heat most of the material generates.