For a film that relies quite heavily on evolutionary science as a plot device, it is great to see how this film is a link to many other films that have evolved from it. But first, we have to look at where it came from. The undeniable king of monster movies to which Creature From The Black Lagoon owes much of its creation is King Kong, made some 21 years earlier.
The story focuses on a small group of scientists who are searching for a fossil of an unknown creature, where one part of it was found but the rest is missing. They travel downriver from where the partial fossil was found to a natural beauty spot called the Black Lagoon. However, unknown to them, the creature is not so much a fossil as something alive that is just behind you. Throughout the early part of the film, the creature is partially spotted lurking around, reaching out for people, but always pullin back. By keeping it largely out of sight and by making the audience more aware than the characters, Jack Arnold, the director, gives genesis to a technique that has been used in many creature features and slasher films later on. The particular examples that came to my mind were Jaws and Halloween, which I doubt would have been made had it not been for Creature From The Black Lagoon.
The creature itself is very clearly a man in a suit, but the lack of special effects does not make this film ridiculous. The greatest scene is the whole film is a swimming scene where the creature, just below the surface, mirrors the movement of a character swimming above it. The underwater camerwork is amazing and still looks good today, over 50 year later. It is hard to underestimate just how important this film is the history of cinema and if you haven't seen it already, I would encourage you to do so.