A Soldier's Story

https://www.youtube.com/watch?v=qzKOb-i9MhA

1984
A black Army investigator (Howard E. Rollins Jr.) travels to a remote military base in the heart of the Louisiana backwoods to look into the mysterious murder of a black sergeant toward the tail end of World War II. Once he arrives, the investigator discovers an Army regiment and an entire community that, despite the beginnings of integration, is still torn apart by race and segregation. He soon learns that on this base, trust is sparse, and secrets are a currency all their own.

https://www.youtube.com/watch?v=35HI5AQYUwg 
In the Heat of the Night 1967

Comment
Dan Waldis
I saw this film when it first was released.  In all my film watching, I still consider this one of the finest films ever made.  The whole tone of the film was so authentically "old South" (of course, the film was certainly created in the perfect time period as well).  The chemistry between Steiger and Poitier was tremendous!  The interaction could be FELT -- unlike what sometimes passes for acting now.  In addition, unlike many present-day films, this cinematic gem did not have to rely on special effects.  And finally, the music.  Quincy Jones composed the sound track and Ray Charles sang the theme song -- it doesn't get better than that!