As The Earth Turns (1938) is a surprisingly charming silent movie which postulates a world war (note the release date, although calling it a release date is problematic) taking place in the near future, in which a mystery entity, displaying immense power and ability to destroy, still cannot make the fighting stop. Two journalists, who happen across information received by US Naval Telegraph, pinpoint the headquarters of the mysterious adversary, and charge in to investigate.
I liked this film a lot. In most silent films, the performs overact outrageously, but not here; likewise, the placards are displayed for just long enough to read. The plot is clever and moves right along, not letting the important step of building empathy with the protagonists slow down the plot. It may have a nearly all-powerful antagonist, but he has his limitations as well, and the plot uses them nicely. The plot has a point: mankind cannot be stopped from fighting by force. The special effects are cheesy, but cheesy in that way that you laugh and joyfully accept them for what they’re trying to achieve.
If you want to see what was apparently a work of love, and not released until after the director died decades later, this might be right up your alley.