A hypnotist and his assistant come to town, presenting an act -- real or contrived -- that features the assistant traveling back in her mind to past lives and revealing details of them to the audience. At the same time, a prehistoric monster is ravaging the community, killing beach bums right and left.
Many have written this film off as worthless and a poor remake. I can't comment on the remake aspect, because I didn't see the original. I would hardly call the film worthless, though. I found it to be highly entertaining and a very captivating story in its own right.
Yes, the film quality is poor, and if you remove the scenes of the beach parties the film doesn't even last a complete hour. But the actors are quite good, especially the man who plays the hypnotist -- giving Montag the Magnificent (from Lewis' "Wizard of Gore") a run for his money. Ultimately, of course, Montag is the better character, but only marginally.
I am still not entirely clear on the connection between the hypnotist and the sea monster (a man in a diving suit and cheesy mask). The link is explained at the end of the film, but doesn't seem to make rational sense. I'd explain that more, but I don't want to give away any twists. I would just like to say if you don't mind low quality 1960s films, this one is worth a viewing.