We all know the big movie villains get a lot of credit and appear in multiple movies - the shark in Jaws, Darth Vader, and before them Dracula, Wolfman, Frankenstein's monster, etc.
But there must be plenty of villains that get forgotten.
I thought Clarence Boddicker (played by Kurtwood Smith) was fantastic in Robocop (1987) - a real psychopath.
Another character who springs to mind is Vilos Cohaagen (Ronny Cox) in Total Recall (1990), I thought he was very good too.
Obviously these and other movie villains do get some critical acclaim but they don't get their own franchise and they rarely get universal praise.
Maybe 'Unsung Movie Villains' is the wrong phrase but hopefully you get what I'm trying to say! XD