The Invisible Man, which comes from the H.G. Wells novel, deserves to be considered alongside Frankenstein, Bride of Frankenstein and Dracula, as the best of classic Universal horror films; perhaps it already is considered such, but it shouldn't necessarily be overshadows by those films, is the point. It has a gritty, mean-streak of its own, akin to Cagney's death at the end of The Public Enemy. Our titular villain isn't merely playing practical jokes and trying to sneak into a naked woman's apartment (Hollow Man, anyone?), but thirsts for the ability of self-improvement, yet goes mad in the process. He then kills policeman, topples a car off of a cliff and derails a train, full of passengers. He's a cold-blooded terrorist.
It shouldn't be surprising that horror films used to actually be about something; picking up where he left off with Frankenstein, Whale is interested in understanding man's relationship to scientific progress and the potentially disastrous consequences that could result under the societal transgressions of a single man. It's all about a fear of the unknown, a fear that scientific progress will lap man's ability to comprehend it. Of course, there are nice sight gags and effects, as when the invisible man (Claude Rains) steals a bike and goes riding down a dirt road. But it isn't camp either; there's humor in the horrific and Whale takes every opportunity to reveal it. Thus, it has a balance modern horror often cannot comprehend. It's funny without being self-aware. It's scary without being bombastic. It possesses subtlety. Too many current filmmakers need to look up the definition.