Radio 4 and it's currently available via their BBC iplayer. I would urge you to go over there and check out their site if you haven't already and bookmark it. The BBC are always a wealth of useful information, many times information regarding our own country and politics our msm shove to the back or ignore completely in favor of "info-tainment".

This is a fascinating piece of history, during a disturbing period of time and it illustrates how seemingly normal people are duped into believing they are really doing the right thing with catastrophic and long lasting results.

I'm not making assumptions here - but I wonder if in 30 years time we won't be hearing a similar documentary "Mother Was A Teabagger", with similar results. Just wondering.