The Bermuda Depths is a Japanese / American co-production 1978 fantasy film originally broadcast as a made-for-TV movie written by Arthur Rankin Jr. of Rankin/Bass fame. Special effects and creature elements were handled by Tsuburaya Productions, most famous for the Ultraman franchise. The movie first aired in the United States January 27, 1978 on ABC, and was later released to theaters in Japan.

Plot

On a Bermuda beach, a sleeping Magnus Dens is approached by a beautiful but mysterious woman, Jennie Haniver, who seems to recognize him. In the meantime, Magnus is dreaming of his childhood, playing on the same beach, watching a turtle egg hatch with his friend Jennie. Jumping a few years later, both are playing with a grown turtle, Magnus carves "J+M" inside a heart on the turtle's shell while Jennie makes a cowrie shell necklace for Magnus. The scene then shifts to young Magnus on the beach spotting Jennie riding the turtle, heading out to open sea and disappearing beneath the water as he calls after her, then shifts again to his nightmare of the night his father, Lionel, was knocked into the water by an unseen horror in the cave beneath the house and part of his house on a cliff crumbling down to the beach as the storm rages on.