aka Madmen of Mandoras
How bad is it? It sat on a shelf for four years before someone released it.
Should you see it? On its merits, no; because people will ask if you've seen it, yes.
This film starts with a title sequence that has the copyright date 1959. The very next sequence is of cars and fashions of the 1960's; that's the first laugh and a sign of what you're in for when watching this. Sixty minutes of tedium later, you'll be waiting for the next laugh, which comes when you find that not only have they saved Hitler's brain, they saved his whole head and it's still barking orders from a fish tank! The film was deemed unreleasable, but someone picked it up on the cheap, added a wrap-around, re-titled it and released it, making it almost pure profit for them. The plot, such as it is, has a neurobiologist who specializes in nerve gas and his daughter disappearing; another daughter and her husband investigate. This leads them to a Caribbean island, where Nazis are planning to take over the world with nerve gas and their leader's head is ready to be put on top of a robot. It's terrible, but the laughs are too far apart for a truly enjoyable experience.