TheLoveBandit
Retired Never Was, Coulda been wannabe
philosophy of a knife, above didnt work
Link works, they just make you go to youtube to see it. I watched the trailer and determined two things
1 - it is about Unit 731, a real and truly horrific time and place in Japan for human atrocities. For those that are interested in the gore and depravity of mankind, read up on this history. I'd say it was a predecessor for the Nazi's experiments on Jews. Here's the wiki on it for some background.
2 - Philosophy of a Knife (2008) appears to be a horror film, meaning it is acting and special effects that APPEAR like acting and special effects (cheap). The trailer had no audio, just unrelenting atmospheric music that becomes annoying when run for the full 4min of the trailer, IMO

There was also The Men Behind the Sun (1995) which covered the same topic but presented itself not as a documentary or horror film, but almost as a film-film where we follow certain characters. While there isn't much plot (some prisoners try to escape iirc, while a soldier questions why he is doing this), there is dialogue (dubbed or subbed, your choice). Also shot in B&W iirc. Not a great film, but did a decent job of covering what was going on but with more of a movie feel to it. I would def recommend TMBtS over PoaK (basaed on the trailer).