

The crew of an experimental underwater nuclear base are forced to struggle for their lives when their explorations disturb a creature who threatens to destroy their base.
Practical Effects
The creature is gloriously rubbery and unashamed.
Production
Tanked sets that actually look underwater, barely.

Director
Sean S. Cunningham
Trivia, insights & behind the scenes
Sean S. Cunningham rushed this into production to beat The Abyss and Leviathan to theaters. He lost anyway.
This bombed so hard it killed underwater horror until Deep Blue Sea, proving some depths should stay unexplored.