The incredible shrinking man (1957)
The cosy, idyllic intro is followed by a brisk, cleverly told escalation where complications with society grow as our hero shrinks. Abruptly, all turns into a primordial fight for survival, ending in a mental revelation with religious overtones.
Well-structured and to the point, you can’t help but feel for the little man. Uneven acting, scenography and special effects in combination with pompous voice-over places this in the B category, though. Maybe in my book.