I don't know what people have against this movie. Okay, so some of the special effects aren't great, but to be honest I prefer films like this which have interesting plots, solid characters and imaginative scenery to the kind of effects-dependent trash Hollywood is currently churning out without care or interest.
The story involves scientists intending to explore under the ocean with the use of a diving-bell. However, after they find a gold statue they, together with most of the crew of their ship, are abducted by a giant octopus and taken to the lost undersea world of Atlantis.
This is a classic and highly entertaining film with good performances from the cast and atmospheric settings with appropriately haunting music.