Otto Preminger's seminal courtroom drama. And by that I mean both definitions 1 and 2.

sem·i·nal/ˈsemənl/
Adjective:
1. (of a work, event, moment, or figure) Strongly influencing later developments.
2. Of, relating to, or denoting semen.

Gets a little "Matlock" on occasion, but I was never bored during the 2.5 hour running time. Older Jimmy Stewart is the best.