This is an underrated cult classic from the 70s, a great decade for atmospheric horror films. The eerie score, excellent location and spooky zombie makeup are all great. A few reviewers have complained about the makeup for the zombies but I thought it was good for the purposes and budget of this film. I assume these naysayers also belong to the "show us more guts" crowd. Some other complaints are about the daylight shooting. Apparently, according to some, this detracts from the movie's effectiveness to scare people. Hogwash. It takes more talent to create atmosphere and terror in broad daylight than at night. The director accomplishes this quite well and deserves to be applauded for it.

The cast is solid. Brooke Adams is a young and sexy lead. Solid support from horror vets Peter Cushing and John Carradine (whose arthritic hands are painful to look at and I can only imagine the poor man's suffering). The male lead is the mustachioed Luke Halpin (from Flipper) and he's very rootable.

On a side note I have to roll my eyes at some of the reviewers bemoaning the lack of gore and guts. This is not a zombie movie in the Romero mold. These are reanimated dead Nazis who kill. They don't eat brains or rip out guts. Why some need to see such visceral imagery to enjoy a horror film is perplexing to me but it takes all kinds I guess.

In the 1970s and 80s, there were quite a few films like "Shock Waves"...films involving Nazi zombies or some other zombies living on some island and which harass a group of tourists. So, when I saw this film on YouTube I thought I'd seen it before...but hadn't. Instead, I saw a film a lot like it...and there's a good chance you have as well!

The picture begins with a short prologue about Nazi super soldiers who were developed by scientists near the end of the war. The credits roll and the story then begins. A young woman is found adrift in a dingy out in what you assume is the Caribbean. She's hysterical at first and when she composes herself, she thinks back to what she's been through...and this extended flashback makes up nearly all the film.

Some tourists are out on a really crappy boat run by a weird old captain (John Carradine). They run adrift on a reef and are stuck. The next day, the captain is missing and everyone else makes there way to shore...as there is an island nearby. But they also discover the captain's body on the way....and that's really not a good sign! They also discover that this abandoned island isn't so abandoned after all, an old German guy with a mega-cool scar on his face (Peter Cushing) is living in what looks like an abandoned mansion. He insists that their timing stinks and they must get off the island ASAP....and then they discover another dead member of their group! He then explains that a ship filled with zombie-Nazi warriors has somehow returned to the island and the soldiers are pretty much unstoppable...so they need to HURRY and leave!!

So is any of this nonsense any good? In other words, although the plot is silly, is it entertaining and well made? While the idea of the film is cool and the make-up and special effects are effective, the characters and what they do are, at times, incredibly stupid. The character 'Norman' is a good example. He's NOT like a real person at all and is simply an annoying clichéd caricature. There's also a super-dopey scene involving a sailboat that simply defies logic. How could these folks be THAT stupid?! It's hard to fathom and group of survivors being this intent on offing themselves!! And, this sort of stupidity keeps occurring...making them too dumb to live! This severely impacts the film....taking it from a neat idea that COULD have worked to yet another schlocky low budget horror film that you could easily skip.

A group of passengers charter John Carradine's boat for a little pleasure cruise and find themselves on a mysterious island where an old SS Commander Peter Cushing is keeping an old experiment going from World War II.

Back in the day when manpower was getting scarce the Nazis started creating zombies out of dead soldiers. A few even got into combat as legends tell. But it was too late and now Cushing sits out on Caribbean island waiting the day when the Reich shall rise again.

The only surprise here is that John Carradine is not the mad scientist, but merely an eccentric old sea salt. The whole thing is fun and quite campy. But in an unintentional way.