Searching for the lost world of Atlantis, Prof. Aitken, his son Charles and Greg Collinson are betrayed by the crew of their expedition's ship, attracted by the fabulous treasures of Atlantis. The diving bell disabled, a deep sea monster attacks the boat. They are all dragged to the bottom of the sea where they meet the inhabitants of the lost continent, an advanced alien race that makes sailors their slaves.
Elenco: Doug McClure , Peter Gilmore , Cyd Charisse , Lea Brodie , Shane Rimmer , John Ratzenberger , Michael Gothard , Hal Galili , Derry Power , Donald Bisset , Ashley Knight , Robert Brown , Daniel Massey .