Ghost Diver (1957)

Сюжет кино: TV Adventure show host goes to South America to recover a lost native treasure after an stone guardian turns up. Hooking up with local native (who we know is a bad guy because he killed the diver who found the statue so he could sell it himself), the host, his son and secretary end up in the middle of an adventure closely akin to film noir.
Picked up on a whim at a nostalgia show this is actually a very good adventure film. Decidedly low budget, there are six characters and very few sets (and a great deal of underwater photography), which is fine since this is a small scale story moves along at a good clip with not a great many twists or turns. Its the sort of film that used to play late at night before cable gave us 500 channels of infomercials. If the film has any real flaws its that some of the underwater sequences can get a bit confusing as to who is doing what. The film is also probably over long at 77 minutes since the film doesn't have enough plot to cover it all.
Worth a look see if you run across it, especially if its at say 2am and you have insomnia. (Oh how I miss those days)