The original Fifties monster movie! This is the story of a team of fossil hunters and anthropologists on an expedition down the Amazon who discover something quite fascinating. They encounter a gill man who has evolved underwater and now has a thing for Julie Adams whom he’s observed swimming. The team get picked off, one by one, as he escapes from their boat and takes her to his cave …. Originally shot for 3D with great sequences by William E. Snyder, the creature is played by Ricou Browning in water, Ben Chapman on land. The non-amphibians are played by Whit Bisssell, Richard Denning and Antonio Moreno. Star Richard Carlson is reunited with director Jack Arnold from the previous year’s It Came From Outer Space and plays a Californian icthyologist based in Brazil who is called in to analyse a skeletal webbed hand. Both he and Adams look very nice in their swimming togs when they take a break from romancing on the tramp steamer. Producer William Alland based the film on a tale he was told during production on Citizen Kane, when Mexican cinematographer Gabriel Figueroa regaled him with a myth of half-human half-fish creatures in the Amazon. His notes, with some aspects of Beauty and the Beast, were expanded into a story treatment by Maurice Zimm and then the screenplay was written by Harry Essex and Arthur A. Ross. Arnold handles this material with appropriate seriousness, getting decent performances in a story that could have descended to the ridiculous. This archetypal Universal production boasts some very influential marine photography particularly the POV shots of Julie Adams which would later resurface in Jaws. A classic, it spawned two sequels.