The Creature Walks Among Us (1956)

Following the Gill-man’s escape from Ocean Harbor Oceanarium in Florida, a team of scientists led by the deranged and cold-hearted Dr. William Barton board the Vagabondia III to capture the creature in the Everglades. Barton is mentally unstable and apparently an abusive husband to his wife Marcia, as he becomes very jealous and paranoid when Marcia is with other men. Their guide Jed Grant makes numerous passes on Marcia (which she constantly rebuffs), with Barton becoming paranoid about the two.

Marcia accompanies Jed and Dr. Tom Morgan on their initial dive to look for the Gill-man, despite her husband’s fierce objections. During the dive, Marcia swims too deep and is overcome with the “raptures of the deep,” temporarily losing her mind, removing all her scuba gear. This forces Jed and Tom to abandon their hunt for the Gill-man to swim back and save her.