A group of holiday makers, taking a boat ride around the Caribbean, run aground on a deserted island after colliding with the wreck of an old WW2 German carrier.
But as well as being shipwrecked, their problems are compounded by a lot of strange goings on. As the skies turn bright orange, the radio stops working, the compass just spins wildly and then the boat's captain (played by John Carradine) just disappears.
The remaining passengers and crew decide to see if there's another way off the island, whereupon they discover an aging German SS Commander (played horror veteran Peter Cushing) who's been living there in voluntary exile. He informs them that he was formerly part of the scientific core, who were working on a batch of genetically enhanced super-soldiers, and the wreck they collided with was the transport that sank with them on it.
It seems though, that these super-soldiers were just a little too well-made. As despite the years under the ocean, the soggy faced, water logged SS troops are not quite dead yet, and having risen up from the depths they proceed to set about the main characters (one of which being Luke Halpin, who played Sandy in the original series of "Flipper") and bumping them off with their bare hands.
Although not overdly gory, as these zombies don't actually eat their victims, this is never-the-less an interesting and well made zombie film. Whilst it might not quite be "Night of the Living Dead", it's certainly a cut above most other films of this ilk. Zombie and B-movie fans will definitely love it.