Dead Poets Society (1989)
Peter Weir's 1989 prep school drama. Robin Williams as the unorthodox English teacher.
Kurtwood Smith played Clarence Boddicker in RoboCop, a villain of such specific unpleasantness that the character is still cited as a benchmark, and the performance is built almost entirely on cheerfulness.
He then appeared in Star Trek VI, Dead Poets Society as a rigid father, and Fortress, working steadily as an authority figure with something wrong underneath.
That 70s Show gave him Red Forman across eight seasons and made him famous to an audience with no idea about RoboCop.
He trained at Stanford and worked in theatre for years before film, which is not what the roles suggest.